THE  BRITISH 
COAL-TAR  INDUSTRY 


THE  BRITISH 
COAL-TAR  INDUSTRY 

ITS  ORIGIN,  DEVELOPMENT, 
AND  DECLINE 


EDITED    BY 


WALTER  M.  GARDNER,  M.Sc.,  F.I.C. 

PRINCIPAL  OF  THE  BRADFORD  TECHNICAL  COLLEGE  ;  EDITOR  OF  THE 
"JOURNAL  OF  THE  SOCIETY  OF  DYERS  AND  COLOURISTS" 


WITH    ILLUSTRATIONS 


PHILADELPHIA 

J.   B.   LIPPINCOTT    COMPANY 
LONDON  :  WILLIAMS  &  NORGATE 


V 


CONTENTS 


INTRODUCTION    ....  vii 

I.   1868.  THE   ANILINE  OR  COAL-TAR   COLOURS.     By   W.    H. 

PERKIN,  F.R.S.     (Cantor  Lectures)        .  .         i 

II.  1870.  THE    ARTIFICIAL    PRODUCTION   OF    ALIZARINE.     By 

Professor  H.  E.  ROSCOE,  F.R.S.    .  46 

III.  1879.  THE  HISTORY  OF  ALIZARIN  AND  ALLIED  COLOURING 

MATTERS.     By  W.   H.  PERKIN,  F.R.S.  ...       54 

IV.  1880.  THE     NEWER     ARTIFICIAL     COLOURING     MATTERS 

DERIVED     FROM     BENZENE.       By     R.     J.     FRISWELL, 

F.C.S.,   F.I.C.         ...                                   .       60 
V.   1881.  INDIGO  AND  ITS  ARTIFICIAL  PRODUCTION.     By  Pro- 
fessor H.  E.  ROSCOE,  LL.D.,  F.R.S.      .         .         .71 
VI.   1885.  THE   COLOURING  MATTERS   PRODUCED  FROM   COAL- 
TAR.     By  W.  H.  PERKIN,  F.R.S 75 

VII.  1886.  RECENT  PROGRESS  IN  THE  COAL-TAR  INDUSTRY.     By 

Professor  Sir  H.  E.  ROSCOE,  M.P.,  LL.D.,  F.R.S.     106 
VIII.  1886.  THE   SCIENTIFIC    DEVELOPMENT    OF    THE    COAL-TAR 
COLOUR    INDUSTRY.     By    Professor   R.    MELDOLA, 
F.C.S.,  F.I.C.  .         .         .121 

IX.  1896.  THE  ORIGIN  OF  THE  COAL-TAR  COLOUR  INDUSTRY 
AND  THE  CONTRIBUTION  OF  HOFMANN  AND  HIS 
PUPILS.  (Hofmann  Memorial  Lecture.)  By  W.  H. 
PERKIN,  Ph.D.,  D.C.L.,  F.R.S.  ,  .  .  141 

X.   1901.  THE     SYNTHESIS     OF    INDIGO.       By     Professor     R. 

MELDOLA,  F.R.S.,  F.I.C.                                  .         .     188 
XI.  1901.  THE    RELATIVE   PROGRESS    OF    THE    COAL-TAR    IN- 
DUSTRY IN  ENGLAND   AND  GERMANY  DURING  THE 
PAST  FIFTEEN  YEARS.       By  ARTHUR   G.   GREEN, 
F.I.C.,  F.CS.                                                              .     189 
XII.  1901.  THE  INDIGO  CRISIS 204 

XIII.  1902.  APPLIED    CHEMISTRY,   ENGLISH   AND    FOREIGN.     By 

Sir  J.  DEWAR,  M.A.,  LL.D.,  D.Sc.,  F.R.S.  .         .222 

XIV.  1903.  THE  RELATION  BETWEEN  SCIENTIFIC  RESEARCH  AND 

CHEMICAL  INDUSTRY.     By  Professor  R.  MELDOLA, 
F.R.S 227 


349277 


vi  THE   BRITISH   COAL-TAR   INDUSTRY 

PAGE 

XV.  1905.  HISTORY    OF    THE    COAL-TAR     COLOUR     INDUSTRY 
BETWEEN     1870     AND     1885.      By     Professor     R. 
MELDOLA,  F.R.S.   ...  .  .228 

XVI.  1906.  NOTE  ON  THE  PERKIN  JUBILEE  .  .     232 

XVII.   1908.  PERKIN     OBITUARY     NOTICE.       By     Professor     R. 

MELDOLA,  F.R.S.   .  ...     233 

XVIII.   1908.  THE  FOUNDING  OF  THE  COAL-TAR  COLOUR  INDUSTRY. 

By  Professor  R.  MELDOLA,  F.R.S.  .         .     234 

XIX.   1908.  LETTER   FROM  PROFESSOR  H.  CARO   TO   PROFESSOR 

R.  MELDOLA,  MAY  1908        .         .         .  -257 

XX.  1910.  TINCTORIAL    CHEMISTRY,    ANCIENT    AND    MODERN. 

By  Professor  R.  MELDOLA,  F.R.S.          .         .         .     259 

XXI.  1910.  PATENT  LAW  IN  RELATION  TO  THE  DYEING  INDUSTRY. 

By  A.  G.  BLOXAM,  F.I.C.       .                                   .     269 
XXII.  1910.  THE    COAL-TAR    COLOUR    INDUSTRY    OF    ENGLAND: 
CAUSES     OF    ITS    PROGRESS    AND    RETARDATION. 
By  I.  SINGER 280 

XXIII,  1914.  THE  ARTIFICIAL  COLOUR  INDUSTRY  AND   ITS   POSI- 

TION   IN    THIS    COUNTRY.      By    F.    M.    PERKIN, 
Ph.D.,  F.I.C.  .  .     298 

XXIV.  1914.  THE   SUPPLY   OF   CHEMICALS   TO   BRITAIN  AND  HER 

DEPENDENCIES.      By    Sir    WILLIAM    A.     TILDEN, 
D.Sc.,  LL.D.,  F.R.S.      .  .     315 

XXV.  1914.  BRITAIN  AND  GERMANY  IN  RELATION  TO  THE 
CHEMICAL  TRADE.  By  WILLIAM  R.  ORMANDY, 
D.Sc.,  F.C.A.  .  335 

XXVI.  1914.  THE  MANUFACTURE  OF  ANILINE  DYES  IN  ENGLAND. 
By  The  Right  Hon.  Lord-Justice  MOULTON,  P.C., 
K.C.,  F.R.S.  .  .351 

XXVII.   1915.  GERMAN   CHEMICAL  INDUSTRY  THIRTY   YEARS   AGO. 

By  The  Right  Hon.  Sir  H.  ROSCOE,  F.R.S.  .     365 

XXVIII.  1915.  THE  MANUFACTURE  OF  DYESTUFFS  IN  BRITAIN.     By 

Professor  W.  M.  GARDNER,  M.Sc.,  F.I.C.      .         .     371 
XXIX.  1915.  THE    CHEMICAL     INDUSTRIES     OF     GERMANY.       By 

Professor  P.  FRANKLAND,  F.R.S.  .         .         -379 

XXX.  1915.  PATENT  LAW  REFORM.     By  J.  W.  GORDON,  K.C.    .     389 
XXXI.   1915.  THE    SUPPLY     OF     DYEWARES.      By     Professor    R. 

MELDOLA,  D.Sc.,  LL.D.,  F.R.S.     ....     401 
XXXII.   1915.  THE    POSITION    OF     THE    ORGANIC    CHEMICAL    IN- 
DUSTRY.    By  Professor  W.  H.  PERKIN,  F.R.S.      .     407 

INDEX  OF  NAMES 429 

INDEX  OF  COLOURING  MATTERS 434 

TABULAR  AND  STATISTICAL  INFORMATION  .  ...     437 


INTRODUCTION 

As  a  side  issue  of  the  war  the  industry  of  the  manufacture 
of  synthetic  dyestuffs  has  been  brought  prominently  before  the 
public  during  the  past  twelve  months.  And  this  has  occurred 
not  because  of  its  magnitude — for  the  annual  value  of  the 
products  used  in  Britain  did  not  much  exceed  £2,000,000, — 
but  because  the  products  were  essential  to  the  carrying  on  of  the 
great  textile  industries  of  the  country,  and  they  were  chiefly 
imported  from  Germany. 

It  was  quickly  recognised  that  our  virtual  dependence  upon 
Germany  for  dyestuffs  jeopardised  our  textile  trade  and  many 
others,  such  as  the  manufacture  of  paints,  which  involve  the  use 
of  pigments  ;  and  the  annual  value  of  the  industries  concerned 
cannot  be  less  than  £220,000,000.  The  stock  of  dyewares  held 
in  this  country  is  never  equal  to  more  than  a  few  months*  supply, 
and  the  processes  involved  in  their  production  are  of  such  a 
nature  that  the  manufacture  cannot  quickly  be  improvised. 
Realising  therefore  that  the  resources  of  private  enterprise  were 
unequal  to  the  task  of  making  the  necessary  provision,  the 
Government  appointed  a  commission  of  inquiry  which  eventually 
resulted  in  the  formation  of  a  State-aided  limited  company — 
British  Dyes  Ltd.  —  established  to  manufacture  or  otherwise 
provide  synthetic  dyestuffs  on  a  scale  commensurate  with  the 
national  requirements. 

The  history  of  the  origin  and  development  of  the  coal-tar 
colour  industry  is  of  great  interest  not  only  to  the  chemist  and 
the  student  of  industrial  economics,  but  also  to  the  politician,  the 
leader  of  industry,  and  even  to  the  general  reader.  To  each  of 

vii 


•viii         THE   BRITISH    COAL-TAR  INDUSTRY 

these  it  has  a  significant  message.  The  industry  which  originated 
and  received  its  early  development  in  this  country  has  grown  to 
be  one  of  great  profit  and  importance,  but  after  a  period  of  much 
prosperity  here  (1856  to  about  1870)  it  became  gradually  more 
and  more  centralised  in  Germany,  and  has  latterly  been  one  of 
her  most  profitable  industries ;  the  average  dividend  paid  by  the 
six  largest  manufacturing  firms  being  upwards  of  20  per  cent,  on 
a  nominal  capital  of  about  £8,000,000,  which  represents  only  a 
small  fraction  of  the  capital  actually  expended,  most  of  which  has 
been  written  off  out  of  profits. 

The  development  in  Germany  of  many  other  associated 
industries  has  been  the  direct  outcome  of  the  success  of  their 
dyestuffs  industry ;  for  example,  the  production  of  synthetic 
medicines,  scents  and  flavourings,  the  manufacture  of  photo- 
graphic drugs  and  of  fine  chemicals  generally,  the  production  of 
artificial  fertilisers  and  of  high  explosives,  and  the  incidental 
production  of  the  necessary  reagents — such  as  sulphuric  acid  and 
caustic  soda — on  an  enormous  scale. 

The  ramifications  of  the  influence  of  the  coal-tar  colour 
industry  in  Germany  are  indeed  most  astonishing,  and  a  close 
investigation  of  the  causes  of  their  success  will  well  repay  those 
who  are  responsible  for  the  future  success  of  British  industry. 

It  is  with  the  object  of  affording  easily  accessible  material  for 
such  an  inquiry  that  this  book  has  been  compiled.  It  comprises 
the  chief  lectures  and  addresses  given  in  this  country  on  the 
subject  since  the  establishment  of  the  industry  by  Perkin  in 
1856  to  the  present  day.  The  papers  are  given  in  chronological 
order,  and  the  book  naturally  divides  itself  into  two  portions,  the 
first  twenty-two  papers  (pp.  i  to  297)  dealing  with  the  history 
and  development  of  the  industry,  and  the  latter  portion  (Papers 
XXIII.  to  XXXIL,  pp.  298  to  427)  dealing  with  the  problem  as 
it  has  presented  itself  since  the  outbreak  of  the  war. 

The  reasons  given  for  the  relative  decline  of  the  British 
industry  and  its  phenomenal  development  in  Germany  are 
numerous  and  varied.  Amongst  the  former  may  be  mentioned 


INTRODUCTION  ix 

the  supposed  lack  of  well-trained  chemists  in  this  country,  our 
admitted  early  neglect  of  chemical  research,  defects  in  our  patent 
laws,  the  excise  restrictions  on  alcohol,  our  fiscal  system,  want  of 
enterprise  and  of  co-operation  amongst  the  British  manufacturers, 
apathy  of  successive  Governments  towards  industry  (as  distinct 
from  commerce),  and  the  early  neglect  of  science  by  the  old  uni- 
versities which  is  not  unconnected  with  a  corresponding  ignorance 
and  neglect  on  the  part  of  our  legislators  and  the  general  mass 
of  citizens. 

These  various  topics  are  all  dealt  with  in  one  or  other  of  the 
papers  reprinted  herein,  and  they  have  a  direct  bearing  not  only 
on  industries  based  on  organic  chemistry — such  as  those  men- 
tioned in  a  previous  paragraph, — but  have  also  a  profound  bear- 
ing on  the  general  question  of  the  relation  of  science  to  industry. 
And  it  cannot  be  too  often  or  too  strongly  stated  that  the 
future  of  British  industry  depends  on  a  full  utilisation  of  science 
in  our  industries. 

One  point  which  is  frequently  lost  sight  of  in  discussing  the 
reasons  for  our  virtual  loss  of  the  coal-tar  colour  industry  is  that 
this  industry  has  not  been  largely  developed  in  any  country  other 
than  Germany.  If  countries  differing  so  widely  in  fiscal,  excise, 
and  patent  laws,  governmental  and  public  appreciation  of  science, 
industrial  conditions,  etc.,  as  Britain,  France,  and  the  United 
States,  are  equally  unable  to  develop  a  particular  industry  which 
flourishes  in  Germany,  this  appears  to  point  to  the  existence  of 
some  specially  favourable  set  of  conditions  in  Germany  rather 
than  to  the  action  of  some  deterrent  condition  in  Britain. 

The  compiler  of  the  book  desires  to  express  his  great  in- 
debtedness to  the  authors  of  the  various  papers,  and  to  the 
editors  of  the  journals  in  which  they  originally  appeared,  for  their 
kind  permission  to  reproduce  them  herein. 

WALTER   M.  GARDNER. 
BRADFORD,  September  ist,  1915. 


L:    1868 
THE   ANILINE    OR    COAL-TAR    COLOURS 

BY  W.  H.  PERKIN,  F.R.S. 

(Cantor  Lectures  :    Journal  of  the  Society  of  Arts,  1868, 
pp.  99,  109,  121) 

I 

COAL  TAR,  BENZOL,  NITROBENZOL,  ANILINE,  AND 
ANILINE  PURPLE  OR  MAUVE 

IN  this  short  course  of  lectures  it  is  my  desire  to  bring  before 
you  a  somewhat  condensed  history  of  the  artificial  colouring 
matters,  generally  known  as  the  "  coal-tar  colours."  By  this 
designation  it  is  not  meant  to  imply  that  colouring  matters 
actually  exist  in  coal  tar,  and  may,  therefore,  be  extracted  from  it, 
but  that  coal  tar  is  the  source  of  certain  products  which,  when 
changed  by  various  chemical  processes,  are  capable  of  yielding 
coloured  derivatives.  You  will  thus  perceive  that  it  is  important 
for  us  to  consider  the  various  means  employed  to  obtain  the  raw 
materials  before  giving  our  attention  to  the  colouring  matters 
themselves.  We  will,  therefore,  at  once  proceed  to  the  considera- 
tion of  "coal  tar,"  its  formation  and  constitution. 

Coal  tar  consists  of  the  oily  fluid  formed  by  the  destructive 
distillation  of  coal,  and  is  obtained  as  a  secondary  product  in  the 
manufacture  of  coal  gas.  Originally,  coal  tar  was  a  great 
nuisance  to  the  gas  manufacturer,  and  it  was  often  a  problem  to 
him  what  he  should  do  with  it.  I  need  scarcely  say  that  this  state 
of  things  is  now  changed.  In  the  gasworks  the  coal  is  distilled 
in  large  retorts,  sometimes  twenty-five  or  thirty  feet  in  length. 
They  are  made  of  fireclay  or  iron,  and  several  are  arranged  in  one 
furnace,  or  oven,  as  it  is  usually  termed.  Each  retort  is  fitted  with 
an  iron  mouthpiece,  from  which  a  vertical  tube  rises,  the  mouth- 
piece also  having  a  door  fastened  with  a  cross-bar  and  screw. 

i 


2  THE   BRITISH   COAL-TAR   INDUSTRY 

When  in  use  these  retorts  are  rapidly  filled  with  coal  by 
means  of  a  proper  scoop,  and  then  the  doors  luted  and  fixed  so 
as  to  be  airtight.  Distillation  commences  immediately,  as  the 
retorts  are  constantly  kept  red-hot.  The  gas  and  other  products 
which  form  pass  up  the  front  vertical  pipe  (connected  with  the 
mouthpiece),  through  a  bend,  and  down  into  a  long  horizontal 
tube,  called  the  "  hydraulic  main/'  Here  most  of  the  oily  pro- 
ducts condense,  and  as  they  accumulate  pass  on  with  the  gas  down 
the  general  main  and  flow  into  a  tank  provided  for  their  reception. 
These  oily  products  constitute  "  coal  tar."  The  coal  gas,  leaving 
this  tar  behind,  passes  on  to  the  condensers,  and  deposits  a  second 
but  smaller  quantity  of  tar,  and  is  then  purified  and  stored  in  the 
gas  holders.  The  gas,  however,  does  not  interest  us  now. 

I  am  here  distilling  some  coal  in  a  small  glass  retort,  the  beak 
of  which  is  inserted  into  one  of  the  openings  of  a  three-necked 
receiver.  The  second  opening  is  connected  with  a  tube,  so  that 
the  gaseous  products  may  be  examined,  whilst  the  third  and  lower 
one  is  fitted  to  a  small  bottle,  in  which  you  see  we  have  already 
obtained  a  quantity  of  an  oily  fluid.  This  is  our  coal  tar. 

Having  now  seen  how  coal  tar  is  produced,  we  will  consider 
of  what  it  consists.  Coal  tar  is  by  no  means  a  definite  body, 
but  contains  a  great  number  of  different  substances,  as  a  glance 
at  the  following  table  will  show  : — 


TABLE  I. — PRODUCTS  OF  THE  DISTILLATION  OF  COAL. 


Name. 

Formula. 

Boiling-point 
Centigr. 

Hydrogen     .... 

HH 

Marsh  gas  (hydride  of  methyl) 

(CH3)H 

... 

Hydride  of  hexyl  . 

(C6H13)H 

65 

Hydride  of  octyl  . 

(C8H17)H 

106 

Hydride  of  decyl  . 

(CioH21)H 

'S3 

Olefiant  gas  (ethylene)  . 

C2H4 

Propylene  (tritylene) 

C8H6 

... 

Caproylene  (hexylene)  . 

C6H12 

55 

(Enanthylene  (heptylene) 

C7H14 

99 

Paraffin 

cjau 

Acetylene 

C2H2 

... 

Benzol 

C6H6 

80-8 

Parabenzol 

C6H6 

97'5 

Toluol  . 

C7H8 

no 

Xylol    . 

C8H10 

139 

THE   ANILINE   OR   COAL-TAR   COLOURS 

TABLE  I. — continued. 


Name. 

Formula. 

Boiling-point 
Centigr. 

Cumol          ...... 

C9H12 

148-4 

Cymol          ...... 

C10H14 

1707 

Naphthaline          ..... 

C10H8 

212 

Paranaphthaline  (anthracene) 

C14H10 

C  TT 

Pyren  ....... 

^64 

^15      4 

... 

Water  

|H}° 

100 

Hydrosulphuric  acid     .... 

{H}S 

... 

Hydrosulphocyanic  acid 

|(CN)}S 

Carbonic  oxide     ..... 

CO 

Carbonic  anhydride       .... 

C02 

.  .  . 

Bisulphide  of  carbon     .... 

CS2 

47 

Sulphurous  anhydride  .... 

SO2 

-    10 

Acetic  acid  

1  (C2H80)  }  ° 

I2O 

Carbolic  acid  (phenol) 

{(C6^5)}° 

188 

Cresylic  alcohol  (cresol) 

i<cSk)}° 

203 

Phlorylic  alcohol  (phlorol)     . 

{  (C8H9)  }  ° 

... 

Rosolic  acid          

... 

Brunolic  acid        

... 

... 

f^i 

Ammonia     .... 

-    33 

(H) 

(  (C6H5)  } 

Aniline         ...... 

182 

Pyridine        ...                  . 

(C5H5)'"N 

II5 

Picoline        ...                  .         . 

(C6Hr)'"N 

T34 

Lutidine       ...                  .         . 

(C7H9)'"N 

Collidine      ...                  . 

(C8Hn)'"N 

170 

Parvoline      ...                  . 
Coridine       ...                  .         . 

(C9H13)'"N 
(C10H15)'"N 

1  88 

211 

Rubidine      ...                  . 

(CnHir)'"N 

230 

Viridine        ...                   . 

(C12H19)'"N 

251 

Leucoline     ...                  . 

(C9Hr)'"N 

235 

Lepidine      ...                  . 

(C10H9)"'N 

260 

Cryptidine    ...                  . 

(CnHnrN 

256 

Pyrrol  ....                  . 
Hydrocyanic  acid 

HC5N 

133 

26-5 

4  THE   BRITISH   COAL-TAR   INDUSTRY 

This  list,  however,  does  not  indicate  all  the  constituents  of  coal  tar, 
but  only  those  which  chemists  have  up  to  the  present  time  (1868) 
succeeded  in  separating  from  it ;  moreover,  when  we  consider 
how  greatly  coal  differs  in  composition,  and  also  that  the  products 
vary  according  to  the  temperature  to  which  the  coal  has  been 
submitted,  it  is  evident  that  coal  tar  must  be  an  almost  endless 
source  of  chemical  products.  Many  would  perhaps  consider 
this  list  a  perfectly  hopeless  jumble  of  names  impossible  to 
impress  upon  the  memory  ;  but,  fortunately,  chemists  are  able  to 
classify  their  products,  so  that  this  formidable  array  of  substances 
may  be  grouped  under  three  or  four  different  heads  only,  and, 
therefore,  their  relationship  being  once  understood,  little  diffi- 
culty is  experienced  in  remembering  their  names. 

Amongst  these  products,  and  at  the  lower  part  of  this  table, 
you  will  observe  a  substance  called  "  aniline."  This  substance 
is  of  great  interest  to  us,  being  one  of  the  principal  sources  of 
the  coal-tar  colours.  Aniline  was  discovered  by  Unverdorben, 
in  1826,  amongst  the  products  of  the  distillation  of  indigo,  and 
from  its  property  of  forming  crystalline  compounds  with  acids 
was  called  "  krystalline."  Afterwards  Runge  obtained  it  from 
the  distillation  of  coal,  and,  because  it  gave  a  blue  coloration 
with  a  solution  of  chloride  of  lime,  called  it  "  kyanol "  or  blue 
oil.  Fritsche,  still  later,  obtained  aniline  by  the  distillation  of 
indigo  with  hydrate  of  potassium,  and  gave  it  its  present  name, 
derived  from  anil,  the  Portuguese  for  indigo.  About  this  time 
Zinin  discovered  a  remarkable  reaction,  by  which  he  obtained 
aniline  from  a  substance  called  nitrobenzol ;  he  called  it,  however, 
"  benzidam."  The  products  obtained  by  these  different  chemists 
were  not  at  first  known  to  be  identical  ;  and  it  was  not  until  Dr 
Hofmann  investigated  the  subject  that  they  were  all  shown  to  be 
the  same  body,  aniline. 

Zinin's  process  for  the  conversion  of  nitrobenzol  into  aniline 
consisted  in  treating  the  nitrobenzol  with  an  alcoholic  solution 
of  sulphide  of  ammonium  ;  this  was  greatly  improved  upon  by 
Bechamp,  who  employed  a  mixture  of  finely  divided  iron  and 
acetic  acid,  in  place  of  sulphide  of  ammonium. 

This  is  a  brief  sketch  of  the  history  of  aniline  up  to  the  time 
of  the  discovery  of  the  mauve  dye  ;  it  was  then  purely  a 
laboratory  product,  and  was  prepared  in  very  small  quantities 
at  the  time,  and  only  when  required  for  scientific  research. 
Chemists  have  always  been  desirous  of  producing  natural  organic 


THE   ANILINE   OR   COAL-TAR   COLOURS         5 

bodies  artificially,  and  have  in  many  instances  been  successful. 
It  was  while  trying  to  solve  one  of  these  questions  that  I 
discovered  the  "  mauve."  I  was  endeavouring  to  convert  an 
artificial  base  into  the  natural  alkaloid  quinine,  but  my  experiment, 
instead  of  yielding  the  colourless  quinine,  gave  a  reddish  powder. 
With  a  desire  to  understand  this  peculiar  result,  a  different  base 
of  more  simple  construction  was  selected,  viz.  aniline,  and  in 
this  case  I  obtained  a  perfectly  black  product  ;  this  was  purified 
and  dried,  and  when  digested  with  spirits  of  wine  gave  the 
mauve  dye. 

You  will  perceive  that  this  discovery  did  not  in  any  way  origin- 
ate from  a  desire  to  produce  a  colouring  matter,  as  is  sometimes 
stated,  but  in  experiments  of  a  purely  theoretical  nature. 

After  showing  this  colouring  matter  to  several  friends,  I  was 
advised  to  consider  the  possibility  of  manufacturing  it  upon  the 
large  scale,  and  was,  eventually,  induced  to  make  the  experiment, 
though,  I  must  confess,  not  without  considerable  fear  of  the 
result,  especially  as  my  chemical  advisers  set  before  me  anything 
but  encouraging  prospects.  In  starting  this  manufacture,  the  first 
difficulty  was  to  decide  upon  the  source  from  which  aniline  could 
be  obtained  at  a  sufficiently  low  price.  It  was  at  once  evident 
that  indigo  was  by  far  too  costly  a  product  for  this  purpose. 
Attention  was  therefore  directed  to  the  extraction  of  aniline  from 
coal  tar,  but  after  very  numerous  experiments  it  was  found  that 
the  difficulty  of  purifying  it  was  so  great,  that  it  was  not  practi- 
cable to  prepare  it  at  a  reasonable  price  from  this  product.  There 
was,  therefore,  but  one  source  left,  namely,  nitrobenzol  ;  but  to 
prepare  aniline  from  this  body  necessitated  the  establishment  of 
a  new  manufacture,  nitrobenzol  at  that  time  not  being  a  com- 
mercial article,  and,  although  it  could  be  produced  in  small 
quantities  without  much  difficulty,  yet  when  tons  were  required 
at  a  limited  cost  many  obstacles  presented  themselves. 

Having  spoken  of  nitrobenzol,  it  will  be  necessary,  before 
proceeding  further,  to  tell  you  something  of  the  body  it  is 
prepared  from,  and  also  how  it  is  made  in  quantity.  Nitrobenzol 
is  produced  from  a  derivative  of  coal  tar  called  benzol — you  will 
see  it  mentioned  in  the  list  of  coal-tar  products.  It  is  composed 
exclusively  of  carbon  and  hydrogen,  and  is  therefore  called  a 
hydrocarbon. 

Benzol  was  discovered  by  Faraday,  in  1825,  one  year  before 
aniline  by  Unverdorben.  Its  existence  in  coal  tar  was  first 


6  THE   BRITISH   COAL-TAR   INDUSTRY 

pointed  out  by  Dr  Hofmann,  in  1 845,  and  afterwards  Mansfield 
showed  that  an  almost  unlimited  supply  might  be  obtained  from 
this  source.  Benzol  is  a  volatile  oil,  boiling  at  a  temperature  of 
80- 8°  C.,  nearly  twenty  degrees  lower  than  water,  and  is  also 
very  inflammable,  burning  with  a  smoky  flame.  When  ignited 
it  cannot  be  extinguished  by  water,  as  it  floats  upon  its  surface. 
Its  vapour,  when  mixed  with  air,  is  explosive.  It  is  also  very 
dense.  This  I  can  easily  show  you  by  decanting  a  small  quantity 
of  benzol  vapour  several  times  from  one  vessel  into  another,  and 
then  igniting  it.  Instances  have  been  known,  when  distilling 
benzol  in  large  quantities,  and  some  leak  in  the  apparatus  has 
occurred,  so  that  its  vapour  has  escaped,  that  it  has  run  along 
the  ground,  and  been  ignited  by  a  furnace  situated  thirty  or 
forty  feet  distant,  and  instantly  run  back  to  the  apparatus.  To 
illustrate  this  I  will  pour  some  benzol  vapour  into  the  top  of  a 
slightly  inclined  trough,  fourteen  feet  long,  at  the  lower  end  of 
which  is  placed  a  lamp.  The  vapour  will  be  seen  to  run  gradually 
down  till  it  reaches  the  lamp,  where  it  ignites,  and  the  flame  in- 
stantly rushes  back  to  the  top  of  the  trough.  One  of  the  most 
remarkable  properties  of  benzol  is,  that  when  cooled  down  to  nearly 
the  freezing  point  of  water,  it  solidifies  to  a  beautiful  crystalline 
mass.  This  property  of  benzol  is  sometimes  taken  advantage  of 
when  it  is  required  in  a  very  pure  state,  as  the  impurities  which 
accompany  it  are  fluid,  and  do  not  freeze  when  cooled  with  ice. 

Benzol  is  often  sold  under  the  name  of  "  benzine  collas,"  for 
the  purpose  of  removing  grease  from  wearing  apparel.  But  let  us 
consider  how  benzol  is  separated  from  the  great  number  of  pro- 
ducts with  which  it  is  associated  in  coal  tar.  The  first  operation 
consists  in  distilling  the  coal  tar,  just  as  it  comes  from  the  gas- 
works, in  large  stills,  holding  one  or  two  thousand  gallons  each  ; 
these  are  often  made  of  old  steam-boilers.  At  first  very  volatile 
and  light  oily  products  come  over,  and  are  collected  until  their 
density  increases  to  such  an  extent  that  they  no  longer  float  upon 
water.  These  constitute  crude  coal-tar  naphtha.  The  distillation 
is  then  carried  on,  and  heavy,  or,  as  they  are  technically  termed, 
"  dead,"  oils  are  collected,  a  residue  of  common  pitch  being  left 
in  the  still.  This  pitch  is  generally  run  out,  and  cast  into  blocks  ; 
but  sometimes  the  distillation  is  carried  on  after  the  dead  oils 
have  been  obtained,  when  a  mixture  of  solid  oily  products  distils, 
nothing  but  a  kind  of  coke  being  left  behind.  These  latter 
substances,  however,  do  not  interest  us  now. 


THE   ANILINE   OR   COAL-TAR   COLOURS         7 

The  light  oil,  or  crude  coal-tar  naphtha,  is  then  purified  by 
one  or  two  alternate  distillations  with  steam  and  treatments  with 
concentrated  sulphuric  acid.  It  is  thus  rendered  a  colourless 
fluid.  Thus  purified,  coal-tar  naphtha  contains,  besides  benzol, 
at  least  four  or  five  other  bodies.  These,  however,  mostly  differ 
from  benzol  in  being  less  volatile  ;  therefore,  the  naphtha  is  again 
distilled,  the  first,  or  more  volatile,  portions  only  being  collected 
for  benzol.  By  repeating  this  process  of  fractional  distillation 
several  times,  commercial  benzol  is  obtained.  Some  manufacturers 
employ  stills  of  a  peculiar  construction,  which  enable  them  to 
obtain  a  good  product  by  a  smaller  number  of  distillations. 

Benzol,  when  treated  with  fuming  nitric  acid  or  aquafortis, 
undergoes  a  remarkable  change.  At  first  the  two  fluids  mix  and 
become  of  a  dark  brown  colour  and  slightly  warm  ;  in  the  course 
of  a  few  moments  red  fumes  appear,  and  the  mixture  enters  into 
ebullition.  During  this  violent  action  the  colour  of  the  liquid 
becomes  lighter  and  ultimately  changes  to  orange.  If  water  be 
now  added  to  this  product,  the  benzol,  which  is  such  a  light 
body,  will  be  seen  to  have  completely  changed  into  a  dense 
yellow  oil  sinking  in  water.  This  oil  is  nitrobenzol.  Nitro- 
benzol  was  discovered  in  1834,  by  Mitscherlich.  It  solidifies 
into  a  crystalline  mass  at  a  temperature  of  about  3°  C.  ;  its 
odour  is  like  that  of  the  oil  of  bitter  almonds,  and  before  the 
introduction  of  coal-tar  colours  it  was  made  in  small  quantities, 
and  sold  under  the  name  of  Essence  de  Myrbane,  for  the  purpose 
of  scenting  soap. 

From  the  energy  with  which  benzol  is  attacked  by  fuming 
nitric  acid,  nitrobenzol  at  first  appeared  to  be  a  most  difficult 
product  to  manufacture  on  the  large  scale,  and  this  difficulty 
seemed  the  greater  when  it  was  found  necessary  that  it  should 
be  made  at  a  moderate  cost.  Moreover,  at  the  time  I  am  now 
referring  to,  fuming  nitric  acid,  sp.  gr.  1-5,  could  not  be  obtained 
in  the  market,  or  only  at  such  a  cost  as  almost  to  preclude  its  use. 
Under  these  circumstances,  two  mixtures  were  experimented 
with  instead  of  the  nitric  acid  in  a  very  concentrated  condition. 
The  first  was  a  mixture  of  nitrate  of  sodium  and  sulphuric  acid, 
the  second  a  mixture  of  ordinary  nitric  acid,  sp.  gr.  1-3,  and 
sulphuric  acid.  The  mixture  of  sulphuric  acid  and  nitrate  of 
sodium  was  preferred,  and  employed  on  the  large  scale. 

The  first  apparatus  used  in  the  manufacture  of  nitrobenzol, 
for  the  preparation  of  aniline  for  the  mauve  dye,  is  shown  in 


8  THE   BRITISH   COAL-TAR   INDUSTRY 

fig.  i.  It  consisted  of  a  large  cast-iron  cylinder,  a,  fitted  with  a 
stirrer,  b,  and  closed  with  a  door,  c,  fastened  by  a  cross-bar  and 
screw,  d.  This  cylinder  was  capable  of  holding  between  thirty 
and  forty  gallons.  It  was  provided  with  two  necks,  e  e  :  one  for 
the  introduction  of  the  benzol  and  sulphuric  acid,  which  were 
supplied  through  a  syphon  tube  ;  the  other  for  the  exit  of 
nitrous  fumes.  This  last  was  connected  with  an  earthenware 
worm,  to  condense  any  benzol  which  might  be  volatilised  by  the 
heat  of  the  reaction.  The  nitrate  of  sodium  was  always  intro- 
duced into  the  cylinder  before  the  door  was  fastened  up  and 
luted.  Until  the  preparation  of  nitrobenzol  was  understood, 
there  was  a  great  amount  of  uncertainty  in  its  manufacture,  and 


FIG.  i. 

several  explosions  occurred,  but  fortunately  without  causing  any 
injury  to  the  workmen  attending  the  apparatus.  These  explosions 
originated  generally  from  the  liberation  of  too  much  nitric  acid 
from  the  nitrate  of  sodium,  by  the  sulphuric  acid,  before  the 
formation  of  nitrobenzol  had  begun,  so  that,  when  it  started,  the. 
chemical  action  set  in  with  such  energy  that  an  explosion  ensued. 
After  a  few  of  these  unpleasant  occurrences,  however,  sufficient 
experience  was  obtained  to  get  the  manufacture  under  control. 
Apparatus  of  a  much  more  extensive  character  has  since  been 
substituted  for  the  cylinders. 

The  process  of  preparing  nitrobenzol  with  a  mixture  of 
sulphuric  acid  and  nitrate  of  sodium  in  place  of  nitric  acid  may 
be  carried  on  very  well  in  this  apparatus,  provided  sufficient 
sulphuric  acid  be  employed  to  produce  an  acid  sulphate  of 
sodium,  as  this  will  be  found  quite  fluid  at  the  close  of  the 


THE   ANILINE   OR   COAL-TAR   COLOURS         9 

operation,  and  can  be  freely  run  out  at  the  small  outlet.  A 
mixture  of  strong  nitric  acid  and  sulphuric  acid  is  now  usually 
employed  for  the  conversion  of  benzol  into  nitrobenzol.  In 
working  by  this  latter  method  the  entire  charge  of  benzol  is  first 
introduced  through  a  large  opening  in  the  lid  ;  this  is  then 
closed  and  the  stirrer  set  moving  ;  the  nitric  and  sulphuric  acids 
are  then  cautiously  run  in  through  small  pipes,  care  being 
taken  not  to  add  too  much  nitric  acid,  until  the  red  fumes  begin 
to  appear.  After  all  the  charge  of  acids  has  been  added,  and  the 
reaction  has  perfectly  ceased,  the  product  is  drawn  off.  At  first 
a  mixture  of  sulphuric  and  nitric  acids  runs  out,  and  then  the 
nitrobenzol  ;  this  is  collected  separately  and  purified,  first  by 
agitation  with  water,  and  then  rendered  perfectly  neutral  by 
means  of  a  dilute  solution  of  soda.  Should  it  contain  any  un- 
converted benzol  this  may  be  distilled  off  by  means  of  steam. 
On  the  Continent  manufacturers  do  not  appear  to  have  succeeded 
well  in  manufacturing  nitrobenzol  when  it  first  became  a  com- 
mercial article  ;  their  difficulty  appears  to  have  arisen  from  the  fact 
that  they  experimented  in  earthenware  vessels,  which  are  both 
dangerous  and  unsuitable,  and  it  was  not  until  information  was 
obtained  from  England,  I  believe,  that  they  were  able  to  produce 
this  body  at  a  moderate  price. 

We  will  now  pass  on  to  the  processes  for  converting  nitro- 
benzol into  aniline.  I  have  already  mentioned  that  Zinin  was 
the  first  who  discovered  that  nitrobenzol  could  be  converted  into 
aniline,  or,  as  he  termed  it,  benzidam.  His  process  consisted  in 
treating  an  alcoholic  solution  of  nitrobenzol  with  ammonia  and 
sulphuretted  hydrogen  ;  but,  although  the  discovery  of  this  pro- 
cess was  one  of  great  importance  from  many  points  of  view,  still 
it  was  very  tedious.  Bechamp,  however,  found  that  by  employing 
a  mixture  of  acetic  acid  and  finely  divided  iron  instead  of  ammonia 
and  sulphuretted  hydrogen,  the  nitrobenzol  was  very  rapidly 
converted  into  aniline,  and  this  process  has  been  found  the  best 
yet  proposed  (1868)  for  manufacturing  aniline  in  large  quantities. 
Many  other  reagents  have  been  suggested,  such  as  arsenite  of 
sodium,  powdered  zinc,  etc.,  but  none  of  them  have  been  found 
so  advantageous  as  iron  and  acetic  acid. 

In  carrying  out  Bechamp's  process,  cylinders  like  those  used 
for  nitrobenzol  (fig.  i)  were  originally  employed.  The  cylinder 
was  set  in  brickwork  and  heated  by  means  of  a  small  furnace, 
iron  borings  were  first  introduced,  and  the  door  fixed  in  its  place, 


io  THE   BRITISH   COAL-TAR   INDUSTRY 

airtight.  One  neck  was  connected  to  the  upper  extremity  of  a 
cast-iron  worm  by  means  of  a  pipe  called  an  adapter  ;  the  second 
neck  being  fitted  with  a  syphon-tube,  for  the  introduction  of  the 
nitrobenzol  and  acetic  acid.  In  working  on  the  large  scale  it  is 
necessary  to  add  the  nitrobenzol  and  acetic  acid  in  small  quantities 
at  a  time,  otherwise  the  reaction  is  so  violent  as  to  almost  burst 
the  apparatus  :  by  working  carefully,  however,  there  is  no  need 
to  fear  any  difficulties,  especially  if  the  stirrer  is  well  used.  By 
the  time  all  the  charge  has  been  introduced,  a  quantity  of  fluid 
will  have  distilled  over  ;  this  is  returned  into  the  cylinder  and 
the  fire  lit,  and  the  aniline  distilled  off. 

The  principal  change  which  has  taken  place  in  this  process 
consists  in  using  high-pressure  or  superheated  steam  for  the 
distillation  instead  of  fire,  and  working  the  apparatus  by  means 
of  a  steam-engine  instead  of  by  hand. 

Aniline  thus  obtained  is  generally  redistilled  with  addition  of 
a  little  lime  or  caustic  soda,  for  the  purpose  of  decomposing 
a  body  called  acetanilide,  which  is  often  produced  in  the  manu- 
facture of  aniline,  especially  if  the  operation  is  conducted  over  a 
fire  instead  of  with  steam. 

Commercial  aniline  generally  appears  of  a  pale  sherry  colour  ; 
when  chemically  pure  it  is  colourless,  but  if  kept  long  it  becomes 
quite  brown.  It  possesses  a  peculiar  odour,  which  is  slightly 
vinous  when  the  aniline  is  pure.  It  burns  with  a  smoky  flame, 
but  is  not  very  inflammable  :  its  boiling-point  is  182°  C.  One 
of  its  most  characteristic  reactions  is  its  power  of  producing  a 
blue  or  blue-violet  coloration  with  chloride  of  lime,  to  which  I 
shall  again  have  occasion  to  refer.  Aniline  differs  entirely  from 
benzol  and  nitrobenzol,  being  perfectly  soluble  in  dilute  acids. 
This  is  owing  to  its  being  an  organic  base,  and  forming  compounds 
with  acids.  Thus  with  hydrochloric  acid  it  forms  hydrochlorate 
of  aniline  ;  with  sulphuric  acid,  sulphate  of  aniline,  etc. 

We  will  now,  in  a  very  rapid  and  general  way,  glance  at  the 
chemical  changes  which  take  place  in  converting  benzol  into 
nitrobenzol  and  aniline. 

Benzol,  as  I  have  already  stated,  is  a  hydrocarbon,  i.e.  a  body 
composed  of  hydrogen  and  carbon  only  ;  it  is  represented  by 

C6H6. 

This  is  treated  with  nitric  acid,  which  contains  the  elements 

HN03. 


THE   ANILINE  OR   COAL-TAR   COLOURS       n 

The  nitric  acid  acts  upon  the  benzol  and  introduces  its  nitrogen 
and  part  of  its  oxygen,  at  the  same  time  removing  hydrogen  and 
forming  water. 

HN03   +   C6H6  =   C6H5N02   +   H2O. 

Nitric  acid.      Benzol.          Nitrobenzol.         Water. 

Nitrobenzol,  when  treated  with  iron  and  acetic  acid,  is  converted 
into  aniline  by  the  influence  of  hydrogen  gas,  in  what  is  termed 
the  nascent  state,  or  the  peculiar  condition  in  which  it  is  when 
in  the  act  of  being  liberated  from  a  compound. 

This  hydrogen  unites  with  the  oxygen  of  nitrobenzol  and 
removes  it  as  water,  and  at  the  same  time  two  atoms  of  hydrogen 
combine  with  the  deoxygenated  nitrobenzol,  forming  aniline. 

C6H5N02   +   H6  =   C6H7N   +   2H2O. 

Nitrobenzol.  Aniline. 

Having  now  seen  the  various  operations  which  require  to  be 
performed  for  the  production  of  aniline  from  coal  tar,  we  are 
prepared  for  the  consideration  of  its  coloured  derivatives.  We 
will,  therefore,  commence  at  once  with  the  first  of  the  coal-tar 
colours,  the  "  mauve  "  dye.  I  have  already  given  you  the  history 
of  its  discovery  ;  I  will  now  tell  you  how  it  is  made. 

First  of  all,  aniline  and  sulphuric  acid,  in  the  proper  propor- 
tions for  the  formation  of  sulphate  of  aniline,  are  mixed  in 
a  large  vat  with  water,  and  boiled  until  perfectly  dissolved. 
Bichromate  of  potassium  is  then  dissolved  in  a  second  large  vat. 
These  two  solutions,  when  cold,  are  mixed  in  a  third  and  still 
larger  vessel,  and  allowed  to  stand  one  or  two  days.  In  this  way 
a  large  quantity  of  a  fine  black  precipitate  is  formed  ;  this  is 
collected  upon  shallow  filters,  well  washed  with  water,  and  then 
dried.  When  dry  it  is  a  most  unpromising  sooty-black  powder, 
and  contains  various  products  besides  the  mauve  ;  the  most 
troublesome  of  these  is  a  brown,  resinous  product,  soluble  in 
most  of  the  solvents  of  the  colouring  matter  itself. 

At  first  this  resinous  substance  was  removed  by  digestion 
with  coal-tar  naphtha  previously  to  the  extraction  of  the  colouring 
matter,  which  was  afterwards  effected  with  methylated  spirits 
of  wine,  and  the  solution  thus  obtained  when  distilled  left  the 
mauve  as  a  fusible  bronze-coloured  mass. 

When  digesting  the  black  precipitate  with  naphtha  or  strong 
spirits  of  wine,  the  operation  had  to  be  performed  in  closed 
vessels  under  pressure  or  in  connection  with  a  condensing 


12  THE   BRITISH   COAL-TAR   INDUSTRY 

arrangement,  otherwise  large  quantities  of  these  valuable  solvents 
would  have  been  lost ;  and  great  difficulty  was  experienced  in 
getting  apparatus  perfectly  tight,  on  account  of  the  "  searching  " 
character  of  these  fluids.  Substitutes  had  also  to  be  found  for 
the  ordinary  materials  employed  by  engineers  for  making  good 
manhole  joints,  and  a  number  of  other  matters  which  are  appar- 
ently of  but  small  importance,  but  it  is  remarkable  the  amount 
of  difficulty  and  annoyance  they  caused.  The  method  of  ex- 
traction has,  however,  been  materially  improved  upon  by  substi- 
tuting dilute  methylated  spirits  of  wine  for  strong,  as  this  weaker 
spirit  dissolves  only  a  small  quantity  of  resinous  matter  but  all 
the  colouring  matter,  so  that  the  digestion  with  coal-tar  naphtha 
is  now  found  unnecessary. 

The  solution  of  the  colouring  matter  in  dilute  spirit  is  placed 
in  a  still  and  the  spirit  distilled  off,  the  colouring  matter  remaining 
behind  in  aqueous  solution  ;  this  is  filtered  and  then  precipitated 
with  caustic  soda.  It  is  afterwards  collected  on  a  filter,  washed 
with  water,  and  drained  until  of  a  thick  pasty  consistence,  and, 
if  necessary,  dried. 

The  solid  mauve  dissolves  very  freely  in  spirits  of  wine, 
forming  an  intensely  coloured  solution  ;  it  is  also  soluble  to  a 
small  extent  in  water,  but  the  aqueous  solution  on  cooling  forms 
a  kind  of  jelly. 

The  formation  of  the  mauve  or  aniline  purple  by  the  action 
of  bichromate  of  potassium  upon  sulphate  of  aniline  is  a  process 
of  oxidation,  and  since  the  publication  of  the  original  specification 
at  the  Patent  Office  a  great  number  of  patents  have  been  taken 
out  for  the  preparation  of  this  colouring  .matter,  in  which  the 
bichromate  has  been  replaced  by  other  oxidising  agents,  as  per- 
oxide of  lead,  permanganate  of  potassium,  peroxide  of  manganese, 
chloride  of  lime,  ferricyanide  of  potassium,  chloride  of  copper, 
etc.  ;  but  I  need  not  make  any  special  remarks  upon  these  various 
processes,  as  experience  has  shown  that  bichromate  of  potassium 
and  a  salt  of  aniline,  the  reagents  first  proposed,  possess  ad- 
vantages over  all  others,  and  are  now  nearly  universally  employed 
for  the  preparation  of  aniline  purple.  The  next  best  process 
appears  to  be  that  of  Dale  and  Caro,  in  which  chloride  of  copper 
is  employed. 

The  affinity  of  aniline  purple  for  silk  or  wool  is  very  re- 
markable, and  if  I  take  some  wool  and  pass  it  through  a  solution 
of  mauve,  you  will  see  how  rapidly  it  absorbs  it,  even  from  a 


THE   ANILINE   OR   COAL-TAR   COLOURS       13 

very  dilute  solution.  Aniline  purple  is  sent  into  the  market  in 
three  different  conditions,  in  paste,  in  solution,  and  in  crystals  ; 
but  the  latter  are  very  rarely  employed,  as  they  are  very  expensive 
and  do  not  offer  corresponding  advantages  to  the  consumer. 

The  mauve  is  the  most  permanent  coal-tar  purple  known, 
especially  with  respect  to  its  power  of  resisting  the  action  of 
light. 

I  will  now  endeavour  to  give  you  some  idea  of  the  approxi- 
mate amount  of  the  various  products  we  have  considered  obtain- 
able from  100  Ibs.  of  coal,  and  for  this  purpose  I  have  arranged 
them  in  the  following  table  with  their  respective  weights  : — 

Ibs.       ozs. 

Coal  .  .  100      o 


Coal  tar 

Coal-tar  naphtha 
Benzol    . 
Nitrobenzol     . 
Aniline  . 
Mauve    . 


10  12 

o       8 

o 

o 

O          2- 
O          O;- 


You  see  the  smallness  of  the  amount  of  colouring  matter 
obtainable  from  coal  or  coal  tar  ;  but  there  is  fortunately  one 
thing  which,  to  some  extent,  compensates  for  this,  and  that  is 
the  wonderful  intensity  of  this  colouring  matter.  1  will  illustrate 
this  remarkable  fact.  I  have  here  a  large  carboy  containing  nine 
gallons  of  water,  and  will  now  add  to  this  a  solution  containing 
one  grain  of  mauve,  and  illuminate  the  liquid  with  the  magnesium 
lamp,  and  you  see  the  single  grain  has  coloured  this  large  bulk 
of  water.  A  gallon  of  water  contains  70,000  grains,  therefore 
nine  gallons  contain  630,000  grains.  This  solution,  then,  contains 
only  one  part  of  mauve  to  630,000  of  water. 

II 

MAUVE,  MAGENTA,  AND  SOME  OF  THEIR  DERIVATIVES 

Aniline  purple  is  sometimes  supplied  to  consumers  in  a  pure 
and  beautifully  crystalline  condition.  This  product  is  found  to 
be  a  salt  of  a  compound,  chemically  termed  an  organic  base. 
This  base  has  been  called  "  mauveine "  ;  it  is  composed  ex- 
clusively of  carbon,  hydrogen,  and  nitrogen,  in  the  following 
proportions  : 

C27H24N4. 


i4  THE   BRITISH   COAL-TAR   INDUSTRY 

Mauveine,  although  the  base  of  aniline  purple,  when  in  solution 
is  not  of  a  purple  but  of  a  dull  violet  shade,  and  in  the  solid 
state  is  a  nearly  black  crystalline  powder.  The  moment,  however, 
mauveine  is  brought  in  contact  with  an  acid  so  as  to  form  a  salt, 
its  solution  changes  to  a  purple  colour.  This  takes  place  even 
with  that  feeble  acid,  carbonic  acid.  I  have  here  a  dilute  solution 
of  mauveine  ;  you  will  observe  the  dull  violet  colour  it  possesses, 
but  if  my  assistant  only  breathes  through  it  a  few  moments  the 
carbonic  acid  of  his  breath  will  combine  with  it,  and  it  will 
acquire  the  ordinary  colour  of  aniline  purple. 

Mauveine  is  a  most  powerful  chemical  body,  and  will  easily 
decompose  ammoniacal  salts.  This  may  be  readily  seen  if  some 
mauveine  be  heated  with  chloride  of  ammonium  and  a  little 
water,  when  an  abundance  of  ammonia  gas  will  be  evolved,  which 
can  be  distinguished  not  only  by  its  odour,  but  by  the  white 
fumes  it  produces  with  hydrochloric  acid. 

The  salts  of  mauveine  are  beautifully  crystalline,  and  possess 
a  splendid  green  metallic  lustre.  The  crystallised  commercial 
product  consists  of  the  acetate.  Mauveine  possesses  one  of  the 
peculiar  properties  of  indigo.  Indigo,  when  treated  with  re- 
ducing agents,  such  as  a  mixture  of  sulphate  of  iron  and  lime, 
is  rendered  nearly  colourless  and  soluble,  but  this  colourless 
indigo,  when  subjected  to  the  oxidising  influence  of  the  atmo- 
sphere, rapidly  becomes  blue  again.  I  here  refer  to  the  indigo 
vat  so  much  used  by  dyers.  Mauveine,  when  treated  in  a 
similar  manner,  is  also  nearly  decolourised,  changing  to  a  pale 
brownish-yellow  fluid,  but  the  moment  this  is  exposed  to  the 
air  it  assumes  its  original  colour  far  more  quickly  than  indigo. 
This  remarkable  fact  may  be  strikingly  illustrated  by  boiling 
an  alcoholic  solution  of  salt  of  mauveine  with  a  few  strips  of 
zinc,  in  a  sealed  tube  from  which  the  air  has  been  previously 
removed.  The  dark  purple  solution  will  gradually  lose  its 
colour,  and  change  to  a  very  pale  yellowish-brown  shade. 

I  have  a  tube  containing  some  aniline  purple  decolourised  in 
this  manner,  and  now  if  I  open  it,  the  air  rushes  in  and  the 
solution  instantly  assumes  the  ordinary  purple  colour. 

Ordinary  indigo  is  quite  insoluble  in  water,  and,  therefore,  its 
property  of  becoming  soluble,  as  well  as  colourless,  when  treated 
with  reducing  agents,  is  of  great  practical  value,  as  the  dyer,  by 
immersing  his  goods  in  this  solution  of  indigo,  and  then  exposing 
them  to  the  oxidising  influence  of  the  air,  gets  the  colouring 


THE   ANILINE   OR   COAL-TAR   COLOURS        15 

matter  firmly  fixed  in  the  fibre  of  his  materials.  But  as  the 
mauve  is  already  soluble  in  water,  this  property  has  not  been 
found  of  any  practical  value. 

Aniline  purple,  when  introduced  as  a  dye,  being  the  first 
colour  of  its  kind,  had  to  encounter  many  prejudices,  and,  on 
account  of  its  peculiar  nature,  required  the  adoption  of  new  or 
modified  processes  for  its  application.  These  difficulties,  however, 
once  overcome,  its  progress  was  very  rapid.  At  first  it  was 
principally  employed  by  the  silk  dyer  and  printer,  its  application 
to  silk  being  comparatively  easy,  but  it  was  not  used  by  the 
calico-printer  till  a  few  years  afterwards. 

I  distinctly  remember,  the  first  time  I  induced  a  calico-printer 
to  made  trials  of  this  colour,  that  the  only  report  I  obtained 
was  that  it  was  too  dear,  and  it  was  not  until  nearly  two  years 
afterwards,  when  French  printers  put  aniline  purple  into  their 
patterns,  that  it  began  to  interest  British  printers. 

It  will  be  seen  that  to  introduce  a  new  coal-tar  colour  after  the 
mauve  was  a  comparatively  simple  matter.  The  difficulty  in  the 
manufacture  of  all  the  raw  materials  had  been  overcome,  as  well 
as  the  obstacles  in  the  way  of  the  practical  applications  of  an 
aniline  colour  to  the  arts. 

We  will  now  turn  our  attention  to  a  colouring  matter  which 
has  often  been  confounded  with  aniline  purple.  I  have 
designated  it  as  "  Runge's  blue,"  as  it  was  first  observed  by 
Runge.  I  have  mentioned  that  Runge,  when  he  first  obtained 
aniline,  termed  it  "  kyanol,"  or  blue  oil,  on  account  of  the  blue- 
coloured  solution  it  gave  with  chloride  of  lime. 

After  discovering  the  mauve,  I  naturally  made  experiments 
with  this  coloured  product  of  Runge's,  to  see  if  it  contained 
aniline  purple,  but  my  experiments  answered  the  inquiry  in  the 
negative.  A  few  years  afterwards,  however,  I  was  puzzled  by 
finding  that  French  manufacturers  were  beginning  to  produce 
aniline  purple  by  the  agency  of  chloride  of  lime  and  a  salt  of 
aniline  ;  being  much  occupied  at  that  time,  I  was  unable  to  look 
carefully  into  the  matter,  and  it  was  not  until  investigating  these 
apparently  opposite  results  a  short  time  since  that  I  was  able  to 
understand  them.  I  will  perform  Runge's  experiments,  and  for 
that  purpose  will  take  a  solution  of  hydrochlorate  of  aniline,  and 
add  to  it  a  very  dilute  solution  of  chloride  of  lime  (taking  care 
not  to  add  too  much).  The  solution  is  now  changing,  and 
getting  slightly  opaque  ;  by  daylight  it  has  an  appearance  like 


1 6  THE   BRITISH   COAL-TAR   INDUSTRY 

indigo,  but  if  I  render  it  clear  by  the  addition  of  alcohol,  and 
place  it  before  the  magnesium  lamp,  it  is  seen  to  be  of  a  brilliant 
colour,  and  nearly  pure  blue,  quite  unlike  aniline  purple. 

I  have  lately  succeeded  in  obtaining  this  blue  product  in  the 
solid  condition,  by  treating  a  solution  of  hydrochlorate  of  aniline 
with  a  dilute  solution  of  chloride  of  lime,  and  precipitating  the 
resulting  colouring  matter  with  common  salt  ;  it  is  thus  obtained 
in  an  impure  condition,  and  may  be  collected  upon  a  filter  ;  by 
treatment  with  cold  ether  or  benzol,  a  large  quantity  of  brown 
impurities  are  separated,  the  colouring  matter  being  left  in  the 
solid  condition.  This  substance  dissolves  in  alcohol,  forming  a 
nearly  pure  blue  solution,  and  is  capable  of  dyeing  silk  a  blue  or 
blue-violet  colour. 

An  alcoholic  solution  of  Runge's  blue  behaves  with  caustic 
potash  quite  differently  from  aniline  purple,  forming  a  brownish- 
red-coloured  solution  instead  of  a  violet.  Therefore,  there  can 
no  longer  be  any  reason  for  confounding  this  body  with  aniline 
purple,  it  being  entirely  different,  both  in  colour  and  chemical 
properties.  But  as  this  colouring  matter  is  produced  by  oxidising 
hydrochlorate  of  aniline  with  chloride  of  lime,  how  is  it  that 
manufacturers  have  succeeded  in  preparing  aniline  purple  from 
the  same  reagents  ?  This  question  I  find  is  very  easy  to  answer  : 
the  manufacturer  has  gone  a  step  further  and  boiled  his  product. 
Now,  if  I  take  a  piece  of  silk  dyed  with  Runge's  blue,  and 
instead  of  boiling  it,  which  would  wet  it  and  make  it  difficult  to 
manipulate,  do  that  which  is  equivalent — steam  it — a  very 
remarkable  change  takes  place,  Runge's  blue  being  changed  into 
the  mauve.  So,  here  we  have  cleared  up  the  mystery,  and  find 
that  by  the  action  of  chloride  of  lime  on  hydrochlorate  of  aniline 
we  first  get  Runge's  blue,  and  then  by  heating  this  blue  we 
change  it  into  mauve.  Runge's  blue  is  a  very  unstable  body, 
and  of  no  practical  value,  its  alcoholic  solution  changing  into 
mauve  in  a  day  or  two.  This  change  takes  place  directly  on 
boiling. 

We  must  now  pass  on  to  another  colouring  matter,  in  name 
well  known  to  all  of  you — I  mean  magenta,  also  called  roseine, 
fuchsine,  aniline  red,  and  various  other  names.  The  discovery 
of  this  body  and  its  manufacture  were  strangely  dependent  upon 
the  source  which  had  been  selected  for  the  preparation  of  aniline 
for  the  mauve.  Had  the  aniline  contained  in  coal  tar,  or  the 
aniline  obtained  from  indigo,  been  employed  for  the  preparation 


THE   ANILINE   OR   COAL-TAR   COLOURS       17 

of  the  mauve,  instead  of  that  prepared  from  commercial  benzol, 
magenta  and  its  train  of  coloured  derivatives  would  in  all 
probability  have  remained  unknown  to  this  present  day,  from  the 
simple  fact  that  magenta  cannot  be  produced  from  pure  aniline, 
a  second  body  being  also  required. 

You  will  observe,  by  reference  to  the  table  of  coal-tar  products, 
that  next  to  benzol  there  is  a  substance  named  toluol,  a  substance 
having  a  boiling-point  not  very  much  above  that  of  benzol.  On 
this  account  toluol  is  always  contained  in  commercial  benzol,  and 
it  possesses  most  of  its  properties.  With  nitric  acid  it  forms 
nitrotoluol,  very  similar  to  nitrobenzol  ;  with  iron  and  acetic 
acid  it  is  converted  into  a  base,  toluidine,  very  similar  to  aniline, 
except  that  it  is  solid  instead  of  liquid  when  pure.  Therefore, 
aniline  prepared  from  commercial  benzol  always  contains  a  little 
toluidine,  and  this  is  the  second  body  requisite  for  the  formation 
of  magenta. 

An  apparatus  for  the  fractional  distillation  of  coal-tar  naphtha 
has  been  devised,  so  that  its  constituents  may  be  almost  com- 
pletely separated  from  each  other,  and  thus  pure  benzol  or  pure 
toluol  may  be  obtained.1  Having  obtained  these  hydrocarbons, 
pure  aniline  and  pure  toluidine  may  be  prepared  and  then  mixed 
in  the  most  suitable  proportions  for  manufacturing  magenta. 
This  process  is  not  very  generally  employed,  however,  but  the 
quality  of  the  mixture  of  aniline  and  toluidine  is  determined  by 
distillation,  noting  the  quantities  which  come  over  at  different 
temperatures.  The  necessity  of  toluidine  as  well  as  aniline  for 
the  production  of  magenta  was  discovered  by  Dr  Hofmann,  who 
found  that  it  could  not  be  produced  by  perfectly  pure  aniline, 
nor  perfectly  pure  toluidine,  but  that  a  mixture  of  these  two 
bases  yielded  it  in  quantity.  Magenta  was  apparently  first 
observed  by  Natanson  in  1856,  when  examining  the  action  of 
chloride  of  ethylene  on  aniline,  and  afterwards  by  Dr  Hofmann 
in  1858,  when  studying  the  action  of  tetrachloride  of  carbon 
on  aniline  ;  but  industrially  the  discovery  of  magenta  was  made 
by  M.  Verguin,  of  Lyons,  in  1859,  three  years  after  the  mauve. 
M.  Verguin's  process  consisted  in  treating  commercial  aniline  with 
a  fuming  liquid,  called  tetrachloride  of  tin,  and  was  first  carried 
out  by  Messrs  Renard  Brothers,  of  Lyons.  Since  1859  patents 
have  been  taken  out  for  the  production  of  this  colouring  matter 
with  aniline,  and  almost  all  chemicals  known,  whether  capable 

1  See  Clarke's  Eng.  Pat.,  5th  June  1863,  No.  1405. 

2 


1 8  THE   BRITISH   COAL-TAR   INDUSTRY 

or  incapable  of  forming  magenta.  I  may  mention  one  process 
which  was  extensively  employed,  and  is  still  used  to  some  extent 
in  Germany,  and  that  is  the  method  of  making  magenta  with 
commercial  aniline  and  nitrate  of  mercury.  With  care  this 
process  works  very  well,  and  the  colouring  matter  produced  is 
of  good  quality.  When  first  introduced,  magenta  prepared  by 
this  method  was  not  purified,  but  sent  into  the  market  in  a  crude 
form,  so  that  before  using  it  the  dyer  had  to  extract  it  with  water. 
In  the  preparation  of  magenta  by  this  process,  all  the  mercury 
of  the  nitrate  of  mercury  employed  is  recovered  in  the  metallic 
state  ;  but  although  this  process  may  possess  some  advantages, 
yet  the  use  of  mercury  salts  is  most  undesirable,  on  account  of 
their  fearfully  deleterious  influence  upon  the  workmen. 

The  process  which  has  almost  superseded  all  others  involves 
the  use  of  arsenic  acid,  as  proposed  by  Medlock,  and  patented 
by  him  in  January  1860.  This  patent  is  notorious  for  the 
amount  of  litigation  it  has  caused,  showing  that  a  patentee  should 
not  only  be  a  discoverer  but  a  lawyer,  and  even  more,  and  able 
to  discover  precisely  how  much  to  claim  and  disclaim  in  his 
patent,  and  also  to  arrange  his  specification  so  that  the  intellects 
of  the  whole  world  may  not  be  able  to  discover  a  single  flaw  in 
his  description  ;  and  it  is  a  misfortune  common  to  inventors  who 
wish  to  thoroughly  protect  themselves,  to  find  that  they  have 
claimed  too  much. 

The  manufacture  of  magenta,  as  now  carried  on,  is  a  very 
simple  process  ;  it  is  conducted  in  an  apparatus  somewhat 
similar  to  that  represented  by  fig.  2. 

This  apparatus  consists  of  a  large  iron  pot,  a,  about  4  ft. 
diameter,  set  in  a  furnace  of  brickwork  ;  it  is  provided  with  a 
stirrer,  by  worked  by  hand.  All  the  gearing  for  this  stirrer  is 
fixed  to  the  lid,  so  that  stirrer,  lid,  and  all  may  be  lifted  away 
by  means  of  a  crane,  or  other  suitable  apparatus.  There  is  also 
a  bent  tube  fixed  into  the  lid,  and  connected  to  a  condensing 
worm,  dy  by  means  of  a  joint,  which  can  be  made  or  broken  at 
pleasure.  In  preparing  magenta,  a  quantity  of  aniline,  containing 
about  25  per  cent,  of  toluidine,  and  a  nearly  saturated  solution 
of  arsenic  acid,  are  introduced  into  this  apparatus,  and  well  mixed 
by  working  the  stirrer  ;  the  proportions  of  the  materials  are  in 
about  the  ratio  of  i  of  aniline  to  1-5  of  a  75  per  cent,  solution 
of  arsenic  acid.  When  these  are  well  mixed  the  fire  is  lighted. 
After  the  product  has  been  heated  for  some  time,  water  begins 


THE   ANILINE   OR   COAL-TAR   COLOURS       19 

to   distil   over,  then   aniline   and  water,  and  lastly  nearly  pure 
aniline. 

This  operation  requires  some  hours  for  completion,  and  this 
is  determined  by  inserting  an  iron  rod,  from  time  to  time,  and 
drawing  out  a  portion  of  the  product  for  examination,  as  well  as 
by  the  amount  of  aniline  which  distils  over.  When  the  heating 
has  been  completed,  a  steam  pipe  is  introduced  into  the  apparatus 
and  steam  blown  through  the  fused  mass  ;  by  this  means  an 
additional  quantity  of  aniline  is  separated.  The  lid  is  then 
liberated  and  lifted,  with  the  stirrer,  from  the  apparatus,  and 
the  product  left  to  cool  before  it  is  removed.  A  more  elaborate 


FIG.  2. 

and  larger  apparatus  is  sometimes  used,  which  possesses  con- 
siderable advantages  over  the  smaller  one.  The  iron  pot  is 
larger,  and  is  provided  with  an  outlet  at  the  side,  which  is  closed 
during  the  operation,  and  the  shaft  of  the  stirrer  is  hollow 
(as  in  the  aniline  apparatus  described  previously),  and  worked 
by  steam.  When  the  operation  of  heating  is  concluded,  steam 
is  blown  down  the  shaft,  and  after  the  addition  of  water  the 
product  is  boiled  and  run  out  of  the  outlet  in  the  side  of  the 
pot ;  by  this  arrangement  it  is  unnecessary  to  disconnect  the 
lid  of  the  apparatus,  and  the  product  does  not  require  to  be 
removed  by  mechanical  means,  as  with  the  apparatus  described 
above. 

The  crude  product  obtained  by  heating  aniline  and  arsenic 
acid  is  next  transferred  to  vats,  boiled  with  water,  and  filtered. 


20  THE   BRITISH   COAL-TAR    INDUSTRY 

Common  salt  is  then  added,  which  precipitates  the  crude 
magenta  ;  this  is  collected  and  dissolved  in  boiling  water,  again 
filtered,  and  the  solution,  on  cooling,  deposits  the  colouring 
matter  in  the  crystalline  condition.  This,  when  recrystallised, 
constitutes  commercial  magenta. 

Commercial  magenta  consists  of  brilliant  crystals,  sometimes 
half  an  inch  in  length,  having  a  beautiful  golden-green  metallic 
appearance  ;  these  dissolve  in  warm  water  almost  entirely,  forming 
an  intense  purplish-red  solution.  Dr  Hofmann  has  carefully 
studied  the  chemical  nature  of  magenta,  and  has  found  it  to 
consist  of  the  salt  of  an  organic  base,  which  he  has  called 
rosaniline.  This  base  may  be  obtained  from  the  commercial 
product,  by  dissolving  it  in  water  and  boiling  it  with  an  alkali, 
or  alkaline  earth,  such  as  ammonia,  potash,  or  lime  ;  it  is  thus 
rendered  nearly  colourless,  and  after  filtration  rosaniline  separates 
from  the  clear  solution,  on  cooling,  in  colourless  crystals.  It 
is  composed  of  carbon,  hydrogen,  and  nitrogen  when  anhydrous, 
but  generally  contains  an  equivalent  of  water  also.  The 
anhydrous  base  has  the  formula  — 


This  colourless  base  immediately  becomes  dark  red  upon 
combining  with  an  acid,  as  I  can  show  you  by  heating  some  with 
acetic  acid,  when  the  colour  is  immediately  developed.  The 
magenta  produced  by  heating  commercial  aniline  with  nitrate 
of  mercury  is  the  nitrate  of  rosaniline  ;  that  produced  with 
arsenic  acid  is  the  arseniate,  but  in  the  process  of  purification 
this  latter  salt  becomes  converted  into  hydrochlorate,  which  is 
the  salt  most  generally  found  in  the  market.  Other  salts  are 
also  commercially  manufactured,  such  as  the  oxalate  and  the 
acetate,  especially  when  a  very  pure  product  is  required  ;  these 
salts  are  generally  prepared  from  pure  rosaniline,  by  combining 
it  with  the  required  acid,  and  crystallising  from  water. 

The  acetate  of  rosaniline  crystallises  in  magnificent  octahedra, 
possessing  the  ordinary  golden-green  metallic  lustre  to  a  very 
high  degree  ;  it  is  also  the  most  soluble  salt  of  rosaniline  known. 
The  affinity  of  magenta  for  animal  fibres  is  very  great  ;  it  does 
not,  however,  resist  the  action  of  light  nearly  to  the  same  extent 
as  the  mauve.  All  the  derivatives  of  rosaniline  also  possess  a 
very  great  affinity  for  animal  fibres,  in  most  cases  quite  equal  to 
that  of  magenta  itself. 


THE   ANILINE   OR   COAL-TAR   COLOURS       21 

When  speaking  of  aniline  purple,  I  showed  you  that  by 
reducing  agents  it  became  colourless,  or  nearly  so,  but  that  the 
original  colour  was  developed  when  it  was  exposed  to  the  oxygen 
of  the  air.  Salts  of  rosaniline  or  magenta  are  also  decolourised 
by  reducing  agents,  but,  unlike  aniline  purple,  the  colour  is  not 
restored  by  exposure  to  the  air.  Dr  Hofmann  has  found  that 
in  this  case  a  new  organic  base  is  produced  which  he  has  called 
leucaniline.  This  substance  differs  only  from  rosaniline  in  con- 
taining an  additional  quantity  of  hydrogen.  It  may  be  recon- 
verted into  rosaniline  by  oxidising  agents  such  as  bichromate 
of  potassium,  etc. 

There  is  another  very  peculiar  reaction  of  rosaniline.  This 
base  when  brought  in  contact  with  hydrocyanic  acid,  instead  of 
forming  a  coloured  hydrocyanate  of  rosaniline,  yields  a  perfectly 
colourless  body,  which  is  not  a  salt  but  a  base.  This  remarkable 
fact  was  discovered  by  Dr  Hugo  Milller,  and  he  has  called  this 
new  body  hydrocyanrosaniline.  We  shall  have  occasion  to  refer 
again  to  this  substance  and  leucaniline. 

In  the  formation  of  magenta,  a  second  product  is  obtained, 
commercially  called  phosphine.  This  substance  was  first  intro- 
duced by  Mr  E.  Nicholson.  Dr  Hofmann  has  investigated  it, 
and  found  it  also  to  contain  an  organic  base,  which  he  has 
called  chrysaniline. 

Phosphine  or  chrysaniline  is  not  capable  of  being  produced  at 
will,  and  the  quantity  formed  in  the  manufacture  of  magenta  is 
variable.  In  shade  it  is  of  rather  a  yellow  orange.  This 
colouring  matter  differs  from  rosaniline,  the  base  of  magenta, 
in  exactly  the  opposite  direction  to  leucaniline,  containing  two 
atoms  less  of  hydrogen.  Leucaniline,  rosaniline,  and  chrysaniline 
are  thus  related  : 

Leucaniline C20H21N3 

Rosaniline C20H19N8 

Chrysaniline    ......     C20H17N3 

The  principal  use  of  phosphine  is  for  the  formation  of  a 
scarlet  with  magenta.  It  is  not  converted  into  magenta,  nor 
decolourised  with  reducing  agents  or  hydrocyanic  acid,  and 
therefore  does  not  seem  to  be  of  the  same  class  of  colouring 

...  & 

matters  as  rosaniline. 

From  the  residues  obtained  in  the  manufacture  of  magenta 
three  new  colours  have  been  obtained  by  Messrs  Girard  and 
De  Laire,  but,  I  am  sorry  to  say,  my  time  will  not  allow  me  to 


22  THE   BRITISH   COAL-TAR   INDUSTRY 

enter  into  the  particulars  of  these  products.  I  believe  they  have 
not  been  commercially  introduced  as  yet. 

Magenta  is  now  more  used  as  a  source  of  other  colours  than 
as  a  dye.  This  has  caused  its  manufacture  to  be  conducted  on 
a  very  extensive  scale,  and  it  is  now  looked  upon  by  the 
manufacturer  as  a  raw  material  much  in  the  same  way  as  aniline 
was  regarded  in  the  early  days  of  aniline  purple. 

We  will  next  consider  some  of  the  derivatives  of  magenta, 
and  the  first  we  will  study  is  aniline  blue  or  bleu  de  Lyon.  If 
aniline  be  treated  with  a  salt  of  rosaniline  or  magenta,  a  remark- 
able change  takes  place  :  at  first  the  colour  gradually  becomes 
purple,  but  afterwards  gets  quite  blue,  ammonia  being  evolved 
at  the  same  time.  This  peculiar  reaction  was  observed  by  MM. 
Girard  and  De  Laire,  who  found  that  this  change  of  colour  was 
due  to  the  formation  of  a  new  body,  which  they  termed  the  bleu 
de  Lyon  ;  intermediate  products  were  likewise  obtained,  to  which 
we  shall  refer  presently.  MM.  Girard  and  De  Laire  patented  their 
process  in  January  1 8  6 1 .  This  new  aniline  blue  is  one  of  the  most 
important  of  the  artificial  colouring  matters,  and  its  manufacture 
has  been  very  much  improved  upon  since  its  discovery.  There 
are  several  circumstances  which  materially  influence  the  beauty 
of  its  tint,  such  as  the  quality  of  the  aniline  and  the  particular 
salt  of  rosaniline  employed  in  its  manufacture.  It  is  found  by 
experience  that  the  aniline  should  be  as  pure  and  free  from 
toluidine  as  possible,  and  that  the  salt  of  rosaniline  should 
contain  a  feeble  acid,  such  as  the  acetate,  valerate,  oleate,  or 
benzoate  ;  but  why  the  latter  is  necessary  chemists  are  unable  to 
understand  at  present.  Practically,  the  various  salts  of  rosaniline 
required  for  the  manufacture  of  the  blue  are  not  prepared 
separately,  but  are  produced  in  the  operation  by  double  decom- 
position, which  is  simply  a  process  of  exchange  ;  thus,  if  acetate 
of  rosaniline  is  required,  a  mixture  of  hydrochlorate  of  rosaniline 
and  acetate  of  sodium  is  employed  ;  these  react  on  each  other, 
and  change  into  acetate  of  rosaniline  and  chloride  of  sodium. 

Aniline  blue  is  manufactured  in  enamelled  iron  pots  heated 
by  an  oil  bath.  A  mixture  of  magenta,  acetate  of  sodium,  and 
aniline  is  introduced  into  the  pots,  the  aniline  being  employed 
in  excess.  When  charged  the  oil  bath  is  heated  up  to  190°  C., 
and  kept  near  that  temperature.  At  first  the  red  colour  of  the 
mixture  changes  slowly,  but  afterwards  with  rapidity.  The 
progress  of  the  operation  is  ascertained  by  removing  the  wooden 


THE   ANILINE   OR   COAL-TAR   COLOURS       23 

plug,  and  withdrawing  a  small  quantity  of  the  product  upon  the 
end  of  an  iron  or  glass  rod,  and  it  is  considered  complete  when 
a  good  blue  colour  has  been  obtained  ;  to  ascertain  this  point 
with  precision,  considerable  experience  is  necessary.  The  excess 
of  aniline  distils  during  this  operation,  and  is  condensed  by  the 
worm,  and  collected  in  a  suitable  receiver,  so  that  it  may  be 
used  again. 

From  the  crude  blue  product  thus  obtained,  which  is  a  fluid 
of  the  consistency  of  treacle,  all  the  different  qualities  of  blues 
found  in  the  market  are  prepared.  The  cheaper  qualities  are 
obtained  by  simply  treating  the  crude  product  several  times  with 
hydrochloric  acid.  This  removes  all  the  free  aniline,  and  most 
of  the  red  and  purple  impurities.  Another  similar  but  more 
effective  process  is  employed  for  the  preparation  of  the  better 
qualities,  and  consists  in  mixing  the  crude  product  with  methy- 
lated spirits  of  wine,  and  pouring  it  into  water  acidulated  with 
hydrochloric  acid,  and  then  thoroughly  washing  with  water  the 
colouring  matter  which  it  precipitates.  But  for  the  purest  kinds 
of  blue  there  are  several  processes  employed  ;  these  are  based 
upon  the  difficult  solubility  of  some  of  its  compounds  in  alcohol. 
In  preparing  these  very  pure  qualities  of  blue,  instead  of  starting 
with  the  crude  product,  one  of  the  purified  blues  is  taken. 

Aniline  blue,  or  "bleu  de  Lyon,"  is  supplied  to  consumers 
as  a  coarse  powder  having  a  coppery  lustre,  or  in  alcoholic 
solutions  ;  it  is  nearly  insoluble  in  water,  and  has  to  be  dissolved 
in  alcohol  before  it  is  added  to  the  dye  bath. 

The  nature  of  this  blue  has  been  determined  by  Dr  Hofmann. 
It  is  found  to  contain,  like  magenta,  a  colourless  base,  becoming 
blue  only  upon  combining  with  acids.  Dr  Hofmann  has  shown 
this  base  to  contain 

^88"tl^'t» 

and  has  called  it  "  triphenylrosaniline."  Like  rosaniline,  it 
becomes  colourless  when  treated  with  nascent  hydrogen,  forming 
a  new  base,  giving  colourless  salts,  as  leucaniline.  The  com- 
position is 

CsgH^Ng. 

The  insolubility  of  aniline  blue  in  water  has  been  found  a 
great  drawback  to  its  use,  because  when  employed  for  dyeing  it 
is  thrown  out  of  solution  in  the  dye  bath,  and  then  mechanically 
adheres  to  the  goods,  so  that  it  afterwards  rubs  off. 


24  THE   BRITISH   COAL-TAR   INDUSTRY 

Mr  Nicholson  has,  however,  discovered  a  process  for  rendering 
this  blue  perfectly  soluble  in  water.  His  process  closely  corre- 
sponds to  that  employed  to  render  indigo  permanently  soluble. 
This,  it  will  be  remembered,  is  effected  by  subjecting  indigo  to 
the  action  of  concentrated  sulphuric  acid,  whereby  a  sulpho  acid 
is  produced. 

Mr  Nicholson  has  found  that  aniline  blue,  when  treated  by  a 
similar  process,  also  forms  a  sulpho  acid,  perfectly  soluble  in 
water,  and  forming  with  alkalies  nearly  colourless  solutions. 
These,  however,  when  decomposed  by  acids,  change  back  to  the 
original  blue. 

This  soluble  blue  is  now  much  used  for  silk- dyeing,  but  by 
dyers  it  is  not  thought  to  be  so  fast  as  the  normal  compound. 
By  some  modification  of  the  process  just  described,  Mr 
Nicholson  has  obtained  another  soluble  blue,  commercially 
known  as  "  Nicholson's  blue."  This  is  now  very  extensively 
employed  in  Great  Britain  for  wool-dyeing,  but  its  application 
does  not  appear  to  be  well  understood  in  France  and  Germany, 
so  that  its  use  there  is  not  so  great  as  in  our  own  country. 

If  a  salt  of  rosaniline  and  aniline  be  heated  together,  and  the 
process  stopped  before  aniline  blue  is  produced,  the  resulting 
product  when  treated  with  dilute  acid  gives  a  colouring  matter, 
which  has  been  called  "violet  imperial."  This  was  at  first 
supposed  to  consist  of  a  mixture  of  blue  and  magenta,  but 
recent  research  has  shown  it  to  consist  of  intermediate  products. 
Very  large  quantities  of  this  colouring  matter  have  been  used, 
but  its  consumption  is  now  rapidly  falling  off,  owing  to  the 
introduction  of  the  new  violets,  about  to  be  described.  A  few 
months  after  the  discovery  of  aniline  blue,  another  colouring 
matter,  called  the  "  bleu  de  Paris,"  was  obtained  by  MM. 
Persoz,  de  Luynes,  and  Salvetat.  These  chemists  found  that 
when  aniline  was  heated  with  tetrachloride  of  tin  for  thirty  hours 
to  1 80°  C.  in  a  sealed  tube,  neither  a  red  nor  a  violet,  but  a  very 
pure  blue,  was  produced.  This  colouring  matter  is  generally 
described  as  being  identical,  or  probably  identical,  with  the  "  bleu 
de  Lyon."  These  blues  are,  however,  widely  different  in  their 
chemical  nature,  as  the  "  bleu  de  Paris  "  is  easily  soluble  in  water, 
and  crystallises  freely  in  needles  of  a  blue  colour,  with  a  coppery 
reflection.  It  consists  of  the  hydrochlorate  of  an  organic  base, 
which  is  precipitated  from  its  solution  by  alkalies  as  a  purplish- 
blue  powder  ;  it  dyes  silk  readily,  and  retains  its  blue  colour  by 


THE   ANILINE   OR   COAL-TAR   COLOURS       25 

artificial  light.  It  is  remarkable  that  the  discoverers  of  the  "  bleu 
de  Paris  "  do  not  seem  to  have  observed  its  difference  from  the 
«  bleu  de  Lyon." 

I  have  prepared  some  of  this  product  with  a  view  to  its 
examination,  but  hitherto  have  been  prevented  from  determining 
its  composition.  I  hope  to  do  so  soon. 

The  "  bleu  de  Paris  "  is,  unfortunately,  difficult  to  prepare  in 
large  quantities,  and  has  never  been  introduced  commercially. 

The  recognition  of  the  nature  of  the  "  bleu  de  Lyon,"  by  Dr 
Hofmann,  led  him  to  study  the  action  of  a  class  of  substances 
upon  rosaniline,  known  to  chemists  as  the  iodides  of  the  organic 
radicals  ;  this  investigation  resulted  in  the  discovery  of  the 
brilliant  colours  known  as  the  Hofmann  violets,  and  of  which  so 
many  shades  can  be  obtained,  from  a  very  red  purple  to  a  nearly 
pure  blue. 

The  substances  generally  used  for  the  preparation  of  the 
Hofmann  violets  from  rosaniline  are  the  iodides  of  methyl  and 
ethyl  :  the  iodide  of  methyl  differs  from  that  of  ethyl  in  a 
practical  point  of  view,  in  being  rather  quicker  in  its  action  ;  it 
is  also  more  volatile.  Both  these  substances  contain  a  remarkable 
element  called  iodine.  This  body  is  found  in  sea-water  and  sea- 
weed ;  its  aspect  is  very  similar  to  that  of  a  metal  ;  one  of  its 
characteristic  properties  is  that  when  heated  it  volatilises  and 
produces  a  beautiful  purple-coloured  vapour,  and  here  we  find 
how  dangerous  a  little  knowledge  is  when  relied  upon.  When 
the  iodide  of  ethyl,  which,  as  I  have  told  you,  contains  iodine, 
was  introduced  for  the  preparation  of  the  Hofmann  violets,  it 
was  stated  in  some  of  our  periodicals  or  daily  papers,  I  do  not 
remember  which,  that  chemists  had  at  last  succeeded  in  fixing 
the  colour  of  iodine,  whereas  the  iodine  has  nothing  whatever 
to  do  with  the  colours  produced  with  the  iodides  of  ethyl  and 
methyl,  but  is  simply  an  instrument  in  bringing  about  the  change 
which  takes  place  in  their  formation  ;  moreover,  these  colours 
can  be  equally  produced  without  using  iodine  at  all.  It  is 
unfortunate  that  the  popular  reports  upon  scientific  matters  are 
generally  so  utterly  untrustworthy.  One  of  the  most  remarkable 
reactions  of  iodine  is  the  blue-violet  colour  it  gives  with  a  solution 
of  starch  ;  this  is  used  as  a  test  for  its  presence  when  in  the  free 
condition,  and  is  remarkably  delicate  ;  it  is  of  no  use  as  a  colour, 
as  it  is  instantly  decomposed  when  heated.  To  prepare  iodide  of 
ethyl,  ordinary  alcohol  is  treated  with  iodine  and  phosphorus  ; 


26  THE   BRITISH   COAL-TAR   INDUSTRY 

,  the  operation  has  to  be  conducted  with  care,  as  iodine  reacts 
upon  phosphorus  with  great  energy  ;  usually  the  alcohol  and 
phosphorus  are  placed  in  a  retort,  and  the  iodine  added  very 
carefully,  and  in  small  quantities  at  the  time.  The  mixture  is 
then  distilled,  and  the  distillate  mixed  with  water,  which  causes 
the  iodide  of  ethyl  to  separate  as  a  colourless  heavy  oil.  Iodide 
of  ethyl  is  very  volatile,  boiling  at  70°  C.  ;  it  has  an  ethereal 
odour,  and  when  pure  is  colourless  and  transparent ;  it  contains 
no  less  than  81  per  cent,  of  iodine.  Iodide  of  methyl  is 
prepared  in  exactly  the  same  manner  as  that  of  ethyl,  substituting 
wood  naphtha,  or  methylic  alcohol,  for  ordinary  alcohol ;  it 
contains  a  still  larger  quantity  of  iodine  than  the  iodide  of  ethyl, 
viz.  89  per  cent. 

For  the  preparation  of  these  substances  on  the  large  scale 
special  apparatus  has  been  devised,  and  sometimes  amorphous  or 
red  phosphorus  is  substituted  for  the  ordinary  kind  ;  but  I  shall 
not  have  time  to  enter  more  fully  into  this  subject.  To  produce 
the  violets,  Dr  Hofmann  heats  pure  rosaniline  with  iodide  of 
ethyl,  or  methyl  and  methylated  spirits  of  wine,  in  a  cast-iron 
digester,  closed  airtight,  with  a  lid  fastened  down  with  screws. 
A  process  very  similar  to  this  is  sometimes  employed,  and 
consists  in  using  a  salt  of  rosaniline,  caustic  alkali,  iodide  of 
ethyl,  and  alcohol.  But  in  Germany  the  ordinary  hydrochlorate 
of  rosaniline  is  employed  with  alcohol,  or  wood  spirit  and  iodide 
of  ethyl,  and  is  found  to  work  very  successfully.  By  employing 
the  rosaniline  itself  a  lower  temperature  is  required  for  the 
formation  of  violet  than  when  using  its  salts  ;  in  fact,  I  have 
found  that  a  mixture  of  iodide  of  ethyl  and  rosaniline  reacts 
even  at  the  ordinary  temperature  if  left  in  contact  for  a  few  days, 
and  produces  a  red  shade  of  violet. 

On  the  large  scale  Hofmann's  violet  is  generally  prepared 
in  deep  cast-iron  vessels,  surrounded  by  a  steam  jacket,  and 
provided  with  a  lid  having  a  perforation,  closed  with  a  screw 
plug.  This  lid  can  be  firmly  fastened  down  with  screws,  the 
joint  being  made  with  a  vulcanised  indiarubber  washer.  This 
apparatus  is  charged  with  a  mixture  of  hydrochlorate  of  rosaniline 
dissolved  in  alcohol  or  wood  spirit,  and  iodide  of  ethyl  or  methyl, 
in  proportion  according  to  the  shade  required.  After  the 
apparatus  is  closed  the  steam  is  allowed  to  enter  the  steam  jacket, 
and  the  heating  continued  for  five  or  six  hours  ;  the  plug  is  then 
removed  from  the  lid  of  the  apparatus,  and  the  alcohol  or  unused 


THE   ANILINE   OR   COAL-TAR   COLOURS       27 

iodide  of  ethyl  distilled  off.  The  resulting  product  is  dissolved 
in  water,  filtered,  and  precipitated  with  chloride  of  sodium,  but 
sometimes  it  is  first  treated  with  caustic  alkali,  to  remove  all  the 
iodine,  so  that  it  may  be  recovered.  Thus  obtained,  the  colour- 
ing matter  is  of  a  golden  lustre  if  of  a  blue  shade,  and  of  a 
greenish  lustre  if  of  a  red  shade. 

Like  all  the  other  colours  we  have  considered,  the  Hofmann 
violets  are  nearly  white  organic  bases,  their  composition  differing 
according  to  the  shade  of  colour,  thus  : 

A  red  shade  is  composed  of  .  .  .  C22H2SN3 
A  red-violet  shade,  of  ....  C24H27N3 
A  very  blue  shade C26H31N8 

The  colours  of  the  Hofmann  violets  are  remarkable  for  their 
brilliancy,  but,  unfortunately,  they  do  not  resist  the  action  of 
light  so  well  as*  might  be  desired  ;  it  is  remarkable,  however, 
that  the  regard  for  fastness  seems  to  have  given  way  to  the 
desire  for  brilliancy. 

In  the  early  days  of  coal-tar  colours  fastness  was  so  much 
talked  about,  that  when  magenta  was  first  introduced  it  was 
thought  by  some  that  it  would  not  be  largely  used  —  how 
different  has  it  proved  to  be  !  Although  not  very  fast  upon 
cotton,  the  Hofmann  violets  are  sufficiently  so  for  woollen  and 
silk  goods,  as  colours  always  resist  the  light  better  when  applied 
to  animal  fibres. 

In  the  formation  of  Hofmann  violets  we  see  that  rosaniline, 
when  treated  with  iodide  of  ethyl,  becomes  blue,  the  red  being 
converted  into  violet ;  but  with  mauveine,  the  base  of  the  mauve, 
exactly  the  reverse  takes  place,  the  mauveine  being  converted 
into  a  much  redder  shade  with  iodide  of  ethyl.  The  colouring 
matter  produced  from  mauveine  and  iodide  of  ethyl  is  com- 
mercially known  as  "  dahlia  "  ;  the  colour  is  intermediate  in  shade 
between  aniline  purple  and  magenta.  The  colouring  matter 
possesses  the  same  character  for  fastness  as  the  mauve,  and  also 
gives  the  same  reactions  with  acids  ;  unfortunately,  it  is  rather 
expensive,  and  has  therefore  not  been  very  extensively  used. 

Lastly,  there  has  been  a  process  proposed  for  the  production 
of  colouring  matters  similar  to  the  Hofmann  violets,  by  first 
converting  the  aniline  into  ethyl-aniline,  a  base  previously  dis- 
covered by  Dr  Hofmann.  It  is  found  that  by  substituting  this 
base  for  aniline,  in  some  of  the  processes  which  have  been  em- 


28  THE   BRITISH   COAL-TAR   INDUSTRY 

ployed  for  the  manufacture  of  magenta,  the  ethyl-aniline  yields 
purple  or  violet  colouring  matters. 

This  process  has  been  patented  by  MM.  Poirrier  and  Chappat, 
but  the  reaction  appears  to  have  been  first  observed  by  M.  E. 
Kopp.  From  the  great  similarity  of  these  colouring  matters 
to  the  Hofmann  violets,  I  need  not  enter  into  any  lengthened 
description  of  their  properties. 

Sea-water  contains,  besides  iodine,  another  remarkable 
element  called  bromine  ;  it  is  a  liquid  giving  off  very  irritating 
orange-coloured  vapours.  This  remarkable  body  yields,  with 
many  hydrocarbons,  a  great  variety  of  compounds.  With 
ordinary  turpentine,  it  acts  with  great  violence  ;  but  if  the  action 
be  moderated  by  the  presence  of  a  large  quantity  of  water,  a 
thick  viscid  oil  is  obtained.  This  body  was  examined  by  Mr 
C.  Greville  Williams,  who  found  it  to  possess  the  formula  — 


I  have  found  that  this  substance,  when  heated  with  a  solution 
of  magenta  in  methylated  spirits,  produces  a  purple  colouring 
matter  of  great  beauty,  commonly  known  as  Britannia  violet  ; 
it  is  very  extensively  employed  for  dyeing  and  printing,  and  can 
be  produced  of  any  shade,  from  purple  to  a  blue  violet. 

The  Britannia  violet  possesses  the  golden-green  lustre  so 
common  to  all  the  aniline  colours.  It  is  easily  fusible,  amorph- 
ous, and  very  soluble  in  water. 

Earlier  in  my  lecture  I  showed  you  the  great  intensity  of  the 
mauve  dye.  I  will  now  make  a  few  experiments,  to  illustrate 
the  great  intensity  of  some  of  the  colouring  matters  we  have 
been  considering  this  evening. 

I  have  here  some  screens  of  white  paper,  on  which  I  have 
dusted  a  very  small  quantity  of  the  solid  colouring  matters  — 
so  small  a  quantity  that  I  daresay  you  can  scarcely  discover  its 
presence.  If  I  now  project  spirits  of  wine  upon  these  screens, 
so  as  to  dissolve  the  colours,  you  will  see  their  remarkable 
intensity. 

Let  us  now  consider  for  a  moment  the  great  rapidity  with 
which  the  discovery  of  new  coal-tar  colours  followed  that  of  the 
mauve  or  aniline  purple. 

Aniline  purple  was  discovered  in  1856  ;  three  years  after- 
wards, in  1859,  the  magenta  was  introduced.  In  1861  we  had 
the  aniline  blue;  in  1863  the  Hofmann  violet;  and  in  1865 


THE   ANILINE   OR   COAL-TAR   COLOURS       29 

the  Britannia  violet.  Thus  we  see  that  all  these  colours  have 
not  only  been  discovered,  but  introduced  commercially,  in  a 
period  of  less  than  ten  years. 

We  have  now  reviewed  the  principal  coal-tar  colours,  but 
there  still  remain  some  important  ones  for  our  consideration  ; 
and  although  some  of  these  are  not  at  present  largely  used, 
yet  it  is  to  them,  perhaps,  that  we  may  look  for  the  future 
development  of  this  branch  of  industry. 


Ill 

VARIOUS  ANILINE,  PHENOL,  AND  NAPHTHALINE  COLOURS — 
APPLICATION  OF  THE  COAL-TAR  COLOURS  TO  THE  ARTS 

The  first  green  colouring  matter  to  consider  is  the  "  aldehyd 

freen,"  which  owes  its  name  to  a  substance  called  "aldehyd" 
eing  employed  in  its  preparation.     I  must,  therefore,  first  tell 
you  what  aldehyd  is. 

Aldehyd  is  a  product  of  the  oxidation  of  alcohol  ;  it  is  a 
volatile  liquid  possessing  a  very  peculiar  odour,  and  was  dis- 
covered by  a  chemist  named  Dobereiner,  but  analysed  by  Liebig. 
It  is  obtained  by  treating  alcohol  with  a  mixture  of  bichromate 
of  potassium  and  sulphuric  .acid,  and  was  generally  prepared  in 
glass  retorts,  but,  now  that  it  is  required  for  colour  making,  the 
glass  apparatus  is  replaced  by  copper  or  leaden  vessels. 

Towards  the  end  of  1861,  M.  Lauth  described  a  reaction  by 
which  rosaniline  could  be  made  to  produce  a  blue  colouring 
matter  ;  but  this  product  was  found  to  be  useless  as  a  dye,  on 
account  of  its  instability.  It  was  produced  by  the  action  of 
aldehyd  upon  a  solution  of  rosaniline  and  sulphuric  acid.  This 
useless  colour  was  afterwards  experimented  upon  by  a  dyer 
named  Cherpin,  who,  after  a  number  of  fruitless  attempts  at 
fixing  it,  told  his  difficulties  to  a  photographic  friend,  who  evi- 
dently thought  if  it  was  possible  to  fix  a  photograph  it  was  possible 
to  fix  anything  else.  He,  therefore,  advised  his  confidant  to  try 
hyposulphite  of  sodium.  On  making  i-this  experiment,  however, 
the  dyer  did  not  succeed  in  fixing  his  blue,  but  found  it  converted 
into  a  splendid  green  dye,  now  known  as  aldehyd  green. 

To  prepare  this  colouring  matter,  a  cold  solution  of  magenta, 
consisting  of  one  part  of  colouring  matter  dissolved  in  a  mixture 
of  three  parts  of  sulphuric  acid  and  one  part  of  water,  is  em- 


30  THE   BRITISH   COAL-TAR   INDUSTRY 

ployed  ;  about  one  and  a  half  parts  of  aldehyd  are  added  by 
degrees  to  this  solution,  and  when  the  whole  is  mixed  it  is  heated 
on  a  water  bath,  until  a  drop  of  the  product  diffused  in  water 
produces  a  fine  blue  coloration.  It  is  then  poured  into  a 
large  quantity  of  boiling  water,  containing  three  or  four  times  as 
much  hyposulphite  of  sodium  as  the  magenta  employed.  After 
boiling  a  short  time  the  product  is  filtered  off  from  a  greyish 
insoluble  residue  which  forms.  The  filtrate  contains  the  green. 
This  process  being  a  very  simple  one,  a  great  number  of  dyers 
now  prepare  the  colouring  matter  as  they  require  it.  It  may, 
however,  be  precipitated  by  means  of  tannin  or  acetate  of  sodium, 
collected  on  filters  and  drained  to  a  paste,  and,  if  necessary,  dried. 
In  both  these  forms  it  is  found  in  the  market. 

The  aldehyd  green  is  principally  employed  in  silk  dyeing.  It 
is  a  splendid  colour,  and  very  brilliant  both  by  day  and  artificial 
light.  The  chemistry  of  this  green  is  at  present  hidden  in 
obscurity,  as  it  is  very  difficult  to  obtain  in  a  chemically  pure 
condition.  But,  like  the  colouring  matter  previously  described, 
it  is  undoubtedly  the  salt  of  an  organic  base  apparently  containing 
sulphur. 

This  base  is  colourless,  or  nearly  so,  and  becomes  changed 
to  the  normal  colour  of  aldehyd  green  upon  the  absorption  of 
carbonic  acid. 

It  will  also  decompose  ammonia  salts,  combining  with  the 
acid  and  becoming  green.  I  have  here  a  solution  containing  the 
colourless  base  of  this  green,  an  ammonia  salt  and  a  little  free 
ammonia.  If  I  pour  it  upon  a  piece  of  white  blotting-paper  it 
does  not  stain  it,  but  if  I  heat  it  the  ammonia  salt  is  decomposed, 
and  we  get  the  green  developed  with  its  ordinary  intensity. 

There  is  another  green  of  an  entirely  different  nature  to 
the  aldehyd  green  ;  it  is  called  iodine  green.  This  colouring 
matter  is  always  produced,  but  in  variable  quantities,  in  the 
preparation  of  the  Hofmann  violets,  from  magenta  and  iodide  of 
ethyl  or  methyl.  Of  late  much  attention  has  been  directed  to 
this  colouring  matter,  and,  by  making  a  few  alterations  in  the 
process  for  preparing  Hofmann  violet,  from  forty  to  fifty  per 
cent,  of  product  can  now  be  obtained  from  the  magenta  used. 
The  iodine  green  is  much  used  for  cotton  and  silk  dyeing  ;  its 
colour  is  bluer  than  that  of  aldehyd  green,  and  it  is,  therefore, 
more  useful,  as  it  yields,  with  the  addition  of  yellow,  a  greater 
variety  of  green  shades. 


THE   ANILINE   OR   COAL-TAR   COLOURS       31 

Iodine  green  contains  an  organic  base  which  is  not  precipitated 
by  alkaline  carbonates.  With  picric  acid  it  forms  a  difficultly 
soluble  picrate,  and  is  generally  prepared  on  the  Continent  as  a 
paste  consisting  of  this  colour  precipitated  with  picric  acid  and 
drained  on  a  filter.  In  England  it  is,  however,  sold  in  alcoholic 
solution.  It  is  a  good  green  by  gaslight. 

The  next  green  I  have  to  bring  before  you  is  a  magenta  deri- 
vative, commercially  called  "  Perkin's  green."  In  its  properties 
it  resembles  more  closely  the  iodine  than  the  aldehyd  green,  but 
differs  from  this  in  its  solubility,  and  in  being  precipitated  by 
solutions  of  alkaline  carbonates,  such  as  carbonate  of  sodium.  It 
is  an  organic  base  which  is  nearly  colourless,  and  is  by  no  means 
a  chemically  powerful  body.  Like  the  iodine  green,  it  is  precipi- 
tated by  picric  acid,  forming  a  picrate  which  crystallises  from 
alcohol  in  small  prisms  with  a  golden  reflection.  This  colouring 
matter  is  principally  employed  for  calico  printing,  and  is  now 
extensively  used.  Thus  you  see  we  have  three  aniline  greens, 
some  useful  for  one,  and  some  for  another  purpose,  so  that  the 
silk  and  cotton  dyer  and  the  calico-printer,  as  well  as  others,  can 
be  supplied.  For  fastness  these  greens  are,  I  think,  quite  as 
good  as  the  violets  ;  the  aldehyd  green,  however,  I  believe, 
resists  light  the  best. 

In  the  formation  of  the  mauve,  or  aniline  purple,  there  is 
always  a  small  quantity  of  a  second  colouring  matter  produced, 
of  a  rich  crimson  colour,  similar  to  that  of  safflower.  Several 
years  ago  I  examined  this  substance,  and  found  it  to  dye  silk 
a  remarkably  clear  colour,  but  owing  to  the  press  of  other 
matters,  and  the  very  small  quantities  in  which  it  could  be 
obtained,  1  did  not  give  it  any  further  attention.  By  a  new 
process,  however,  it  can  now  be  produced  in  somewhat  larger 
quantities,  and  endeavours  are  being  made  to  introduce  it  to  the 
arts,  as  it  produces  beautiful  tints  of  pink  upon  silk  and  cotton, 
and,  moreover,  can  be  used  for  printing  cotton,  silk,  and  wool 
processes,  to  which  safflower  cannot  be  applied  as  it  will  not 
bear  steaming.  This  aniline  pink  or  crimson  is  a  beautiful 
chemical  body,  crystallising  in  small  prisms  possessing  a  golden- 
green  lustre.  It  is  soluble  in  alcohol,  and  also  in  water  ;  it 
produces  solutions  remarkable  for  their  fluorescence — so  much 
so,  that  by  certain  lights  they  appear  as  if  filled  with  a  precipitate. 
In  colour  and  fastness  it  is  equal  to  safflower,  and,  should  it  be 
found  possible  to  manufacture  it  at  a  moderate  price,  I  should 


32  THE   BRITISH   COAL-TAR   INDUSTRY 

imagine  it  would  entirely  supersede  that  colouring  matter, 
especially  as  it  is  not  affected  by  alkaline  solutions. 

There  is  a  product  in  the  English  market,  supposed  to  be  an 
aniline  colour,  called  "  Field's  orange,"  after  its  discoverer,  Mr 
Frederick  Field.  Its  properties  are  those  of  a  nitro-acid,  but,  as 
its  preparation  has  not  been  described,  of  course  I  cannot  tell 
you  anything  about  it.  With  alkalies  it  forms  a  rich  orange- 
coloured  solution,  but  by  the  addition  of  an  acid  it  is  precipitated 
as  a  pale  yellow  powder. 

Field's  orange  is  a  very  useful  colouring  matter,  having  a 
great  affinity  for  animal  fibres,  and  is  extensively  used  for  wool- 
dyeing,  as  it  resists  the  action  of  light  very  well. 

We  now  come  to  a  colouring  matter  of  a  very  indefinite 
nature.  I  refer  to  aniline  black.  This  substance  appears  to  be 
closely  allied  to  the  insoluble  part  of  the  black  precipitate  formed 
in  the  manufacture  of  the  mauve.  This  precipitate,  however, 
always  contains  oxide  of  chromium,  which  cannot  exist  in  the 
aniline  black  generally  employed,  as  no  chromium  compound  is 
used  in  its  preparation  ;  but  as  copper  compounds  are  used,  it 
may  be  that  aniline  black  represents  the  black  precipitate  with 
the  oxide  of  chromium  replaced  by  the  oxide  of  copper,  or  it 
may  even  be  that  in  either  case  the  metallic  oxide  is  not  an 
essential  part  of  this  black  substance. 

Aniline  black  is  perfectly  insoluble,  and  has,  therefore,  to  be 
formed  upon  the  fibre  when  employed  for  calico-printing.  As 
we  shall  have  to  refer  to  its  application  to  dyeing  and  printing,  I 
will  not  make  any  further  remarks  upon  it  just  now. 

From  mauve  and  magenta,  chocolate,  maroons  and  browns  are 
prepared  ;  but  as  they  are  of  secondary  importance  as  yet,  I  will 
only  just  mention  one  or  two  of  the  methods  of  preparing  them. 

One  of  the  processes  for  preparing  chocolate  from  magenta  is 
by  the  action  of  nitrous  acid,  but  care  has  to  be  taken  to  watch 
the  progress  of  the  operation,  and  to  stop  it  when  the  required 
shade  has  been  obtained.  Another  process  consists  in  heating 
magenta  with  hydrochlorate  of  aniline  to  a  temperature  a  little 
above  200°  C.  The  product,  when  purified,  produces  a  maroon 
colour.  Browns  are  generally  obtained  from  a  residue  of 
magenta  making. 

All  the  colouring  matters  we  have  considered  up  to  the 
present  time  are  derivatives  of  aniline  and  toluidine,  and  con- 
stitute nearly  all  the  colours  of  the  rainbow. 


THE   ANILINE   OR   COAL-TAR   COLOURS       33 

By  the  action  of  nascent  hydrogen  upon  dinitrobenzol,  Mr 
A.  H.  Church  and  myself  obtained,  in  1857,  a  crimson  colouring 
matter,  which  was  named  nitrosophenyline.  I  have  lately  made 
a  few  new  experiments  upon  this  remarkable  body,  and  find  that 
it  has  an  affinity  for  pure  cotton,  dyeing  it  of  a  clear  cerise  colour, 
considerably  less  blue  in  tint  than  safflower.  With  very  dilute 
acids,  this  colouring  matter  forms  a  blue  solution  ;  with  less 
dilute  acid,  a  crimson  colour  ;  and  with  concentrated  sulphuric 
acid,  a  green  colour.  It  is  difficult  to  judge  of  the  probable 
utility  of  this  colouring  matter,  as  it  is  so  difficult  to  obtain  in 
quantity  by  the  present  process.  I  may  mention  that  my  new 
experiments  with  this  substance  have  caused  me  to  doubt  the 
purity  of  the  product  examined  by  Mr  Church  and  myself  ;  and 
this  is  not  remarkable  when  we  consider  how  few  methods  of 
purifying  artificial  colouring  matters  were  known  at  the  date  of 
our  experiments,  as  well  as  the  small  amount  of  substances  at 
our  disposal. 

We  now  turn  to  a  product  very  different  from  aniline,  though 
related  to  it  in  some  respects  very  closely.  On  the  table  you 
will  see  a  coal-tar  product  called  "  phenol  "  or  "  carbolic  acid." 
It  was  discovered,  a  long  time  since,  by  Runge,  and  afterwards 
studied  by  a  great  number  of  chemists.  It  is  only,  however, 
during  the  last  few  years  that  it  has  been  introduced  into  com- 
merce in  a  pure  condition,  thanks  to  Dr  Crace  Calvert. 

Phenol  or  carbolic  acid  is  a  splendid  crystalline  body,  pos- 
sessing many  most  interesting  properties  ;  but  I  must  confine 
myself  to  a  short  account  of  its  coloured  derivatives  only. 

Carbolic  acid,  when  treated  with  nitric  acid,  yields  a  yellow 
acid,  known  as  picric  acid.  The  substance  can  be  produced  from 
many  other  bodies  besides  carbolic  acid,  and  when  first  employed 
for  dyeing  purposes  was  generally  prepared  from  the  resin  of 
the  Xanthorrhea  hastilis,  but  now,  owing  to  the  cheapness  and 
purity  of  carbolic  acid,  I  believe  it  is  exclusively  used  in  its 
manufacture.  Picric  acid  requires  care  in  its  preparation,  if 
phenol  and  strong  nitric  acid  be  employed,  as  the  action  is  very 
violent.  Pure  picric  acid  is  of  a  very  pale  yellow  colour  ;  it  is 
employed  principally  for  silk-dyeing,  the  colour  it  produces  on 
silk  being  much  darker  than  that  of  the  acid  itself.  Picric  acid 
has  a  very  bitter  taste,  and  by  some  it  is  said  to  be  a  great 
improvement  upon  hops  in  the  manufacture  of  bitter  beer, 
especially  as  it  has  been  proposed  as  a  tonic  in  place  of  quinine. 

3 


34  THE   BRITISH   COAL-TAR   INDUSTRY 

Picric  acid  forms  beautiful  yellow  salts,  the  most  interesting 
being  that  of  potassium.  This  salt  is  extremely  insoluble  in 
water,  and  very  explosive  ;  it  has  been  proposed  as  a  substitute 
for  gunpowder  for  charging  shells.  Picric  acid,  under  the 
influence  of  cyanide  of  potassium,  is  perfectly  decomposed,  and 
changed  into  a  new  compound  called  isopurpuric  acid,  a  substance 
isomeric  with  murexide.  The  potassium  salt  of  this  compound 
is  very  explosive,  and,  to  avoid  danger,  it  is  generally  supplied 
in  a  moist  condition,  and  mixed  with  glycerine.  It  produces  a 
kind  of  maroon  colour  upon  wool,  but  I  do  not  think  it  has 
been  extensively  used  up  to  the  present. 

Runge,  when  experimenting  with  the  products  of  the  dis- 
tillation of  coal,  obtained  two  compounds,  called  by  him  rosolic 
and  brunolic  acids,  which  he  regarded  as  products  existing  in 
coal  tar  ;  I  think  it  most  probable,  however,  that  these  bodies 
were  produced  in  his  process  of  purification,  and  did  not  exist 
ready  formed  in  coal  tar. 

Rosolic  acid  was  afterwards  examined  by  Dr  Hugo  Mailer, 
who  obtained  it  from  crude  carbolate  of  calcium,  which  had 
been  exposed  to  the  oxidising  action  of  the  air.  This  process, 
however,  does  not  yield  rosolic  acid  in  quantity  ;  but  in  1861, 
Kolbe  and  Schmitt  described  a  method  of  producing  this  sub- 
stance, by  heating  a  mixture  of  oxalic,  carbolic,  and  sulphuric 
acids.  It  is  stated,  however,  that  this  process  was  discovered 
by  M.  Jules  Persoz,  in  1859.  ^  ls  by  this  method  that  rosolic 
acid  is  now  manufactured. 

Commercial  rosolic  acid,  commonly  called  aurine,  is  a 
beautiful  brittle  resinous  substance,  having  a  slight  green  metallic 
lustre  ;  when  pure  it  may  be  crystallised,  and  if  pulverised  forms 
a  scarlet  orange  powder.  Its  solutions  are  of  an  orange  colour, 
but  change  with  alkalies  to  a  most  magnificent  crimson.  It 
has  not  been  found  capable  of  very  many  applications  in  dyeing 
and  printing,  although  it  produces  very  good  orange  shades, 
and  with  magenta  it  makes  a  very  good  scarlet. 

The  great  difficulty  in  applying  rosolic  acid  to  the  arts  is 
owing  to  the  easy  solubility  of  its  salts  in  water.  It  appears  to 
be  closely  allied  to  rosaniline,  as  it  has  lately  been  found  possible 
to  obtain  it  from  this  colouring  matter. 

When  heated  with  ammonia,  in  a  closed  vessel,  to  120°  to 
140°  C.,  rosolic  acid  permanently  changes  into  a  new  colouring 
matter  of  a  crimson  shade,  called  peonine  or  coralline.  This 


THE   ANILINE   OR   COAL-TAR   COLOURS       35 

forms  beautiful  tints  upon  silk,  similar  to  safflower,  provided 
it  is  kept  slightly  alkaline,  but  if  treated  with  the  least  quantity 
of  acid  the  freshness  of  its  colour  is  destroyed.  When  heated 
with  aniline  this  colouring  matter  undergoes  a  similar  change 
to  magenta,  being  converted  into  a  blue  called  azuline.  This 
colouring  matter,  as  well  as  coralline,  was  discovered  by  M.  Jules 
Persoz,  and  patented  by  MM.  Guinon  Mamas  &  Bonnet  in  1862. 
Azuline,  when  in  the  solid  state,  presents  a  coppery-coloured  sur- 
face ;  it  is  soluble  in  alcohol,  but  difficultly  so  in  water.  It  is  not 
manufactured  now,  having  been  replaced  by  the  more  brilliant 
blues  obtained  from  rosaniline,  and  described  previously. 

We  must  now  turn  our  attention  to  another  series  of  coal- 
tar  colours,  derived  from  a  beautiful  product  called  naphthaline. 
You  will  see  it  on  the  table  of  coal-tar  products  ;  it  is  a  hydro- 
carbon containing 

CioH8 » 

and  may  be  obtained  in  any  quantity.  It  is  remarkable  for  the 
readiness  with  which  it  sublimes,  and,  like  benzol  and  toluol, 
it  yields  with  nitric  acid  a  nitro-compound  called  cc  nitronaphtha- 
line,"  a  beautifully  crystalline  body,  and  this,  with  iron  and  acetic 
acid,  yields  an  organic  base  called  "  naphthylamine."  This  base 
is  solid,  and  beautifully  crystalline,  but  possesses  a  very  dis- 
agreeable odour. 

Mr  Church  and  myself  obtained  from  a  salt  of  "  naphthyl- 
amine "  and  a  mixture  of  nitrate  of  potassium  and  potash,  a 
beautiful  substance  crystallising  in  orange  needles  with  a  green 
lustre.  It  is  called  by  a  rather  long  name, "  azodinaphthyldiamine." 

This  substance  is  a  feeble  organic  base,  and  dissolves  in 
alcohol,  forming  an  orange-coloured  solution,  which  changes 
to  a  splendid  violet  colour  upon  the  addition  of  hydrochloric 
acid.  It  has,  however,  been  found  useless  as  a  dye,  because 
the  purple  colour  only  exists  in  the  presence  of  free  acid,  and 
the  orange  colour  of  the  base  itself  is  liable  to  turn  brown  when 
exposed  to  the  light.  It  would  appear  probable,  however,  that 
azodinaphthyldiamine  may  become  useful  as  the  starting-point  for 
new  colouring  matters,  as  I  have  lately  succeeded  in  producing 
from  it  a  very  promising  crimson  substance,  possessing  a  con- 
siderable affinity  for  animal  fibres. 

A  very  beautiful  yellow  colouring  matter  has  been  obtained 
by  Dr  Martius  from  naphthylamine,  somewhat  similar  to  picric 
acid,  but  of  a  much  more  intense  colour.  It  is  prepared  by 


36  THE   BRITISH   COAL-TAR   INDUSTRY 

treating  hydrochlorate  of  naphthylamine  with  nitrite  of  potassium  ; 
by  this  means  a  substance  known  as  diazonaphthol  is  obtained  ; 
this  is  then  heated  with  nitric  acid,  and  is  transformed  into  the 
new  yellow,  chemically  known  as  dinitronaphthol.  This  sub- 
stance is  commercially  called  Manchester  yellow.  It  possesses 
the  properties  of  an  acid.  The  commercial  compound  consists 
of  a  beautifully  crystalline  calcium  salt,  soluble  in  water,  and 
dyeing  silk  or  wool  a  magnificent  golden-yellow  colour. 

Owing  to  an  increasing  demand  for  benzoic  acid,  experiments 
have  lately  been  made  with  a  view  of  obtaining  it  from  naphthal- 
ine instead  of  gum  benzoin,  etc.  For  this  purpose  experiments 
were  made  with  an  acid  derived  from  naphthaline,  called  phthalic 
acid,  which,  when  carefully  heated  with  lime,  is  found  capable  of 
yielding  benzoate  of  calcium,  from  which  benzoic  acid  can  be 
prepared.  But  as  in  these  processes  secondary  compounds  are 
formed,  which  interest  us  this  evening,  I  will  briefly  describe  the 
process  employed  for  obtaining  these  various  substances. 

First  of  all,  naphthaline  is  heated  with  a  mixture  of  chlorate 
of  potassium  and  hydrochloric  acid  ;  in  this  way  a  mixture  of 
chloronaphthaline  and  bichloronaphthaline  is  obtained.  These 
products  are  then  heated  with  nitric  acid,  and  yield  a  mixture  of 
phthalic  acid  and  a  substance  called  the  chloride  of  chloroxy- 
naphthyl.  The  phthalic  acid  is  converted  into  the  calcium  salt, 
and  heated  with  slaked  lime  to  a  temperature  of  350°  or  370°  C., 
to  convert  it  into  a  benzoate. 

It  is,  however,  the  chloride  of  chloroxynaphthyl  which 
interests  us  now.  This  substance,  when  heated  with  an  alkali, 
yields  the  salts  of  an  acid  called  chloroxynaphthalic  acid,  which 
may  be  obtained  in  a  free  state  by  means  of  hydrochloric  acid. 
When  pure,  chloroxynaphthalic  acid  is  a  pale  yellow  crystalline 
powder,  forming  beautiful  compounds  with  baryta,  zinc,  and 
copper.  It  dyes  wool  a  scarlet  colour.  The  great  interest  of 
this  substance  consists  in  its  supposed  relationship  to  alizarine, 
the  colouring  matter  of  madder,  the  only  difference  in  composition 
of  chloroxynaphthalic  acid  and  alizarine  being  in  the  former 
containing  an  equivalent  of  chlorine  in  place  of  hydrogen,  thus  : 

C10H6O3  .         .         .     Alizarine. 

C10(H5C1)O8      .         .         .     Chloroxynaphthalic  acid. 

Many  endeavours  have  been  made  to  remove  this  chlorine, 
and  to  put  hydrogen  in  its  place,  with  the  hopes  of  producing 


THE   ANILINE   OR   COAL-TAR   COLOURS       37 

alizarine  ;  but,  up  to  the  present  time,  no  definite  results  have 
been  obtained. 

I  am  inclined  to  think  that,  although  this  relationship 
of  composition  exists  between  these  bodies,  yet  that  their 
chemical  nature  is  quite  dissimilar.  We  generally  find  that 
chlorinated  bodies  have  similar  properties  to  those  from  which 
they  are  derived  or  represent.  Chloroxynaphthalic  acid, 
however,  does  not  appear  to  possess  properties  similar  to 
alizarine.  This  acid  dyes  wool  readily  without  a  mordant ; 
alizarine  only  slightly  stains  it.  When  boiled  with  cloth  prepared 
with  alumina,  or  iron  mordants,  it  scarcely  produces  any  change, 
while  alizarine  yields  intense  colours. 

This  process  of  preparing  benzoic  and  chloroxynaphthalic 
acids  is  carried  out  on  a  large  scale  in  France,  by  MM.  P.  & 
E.  Depouilly,  to  whom  I  am  indebted  for  the  specimens  of  these 
products  shown  in  this  lecture.  Some  of  the  chloroxynaphthalates 
are  beautifully  coloured  salts,  and  are  used  as  pigments. 

Laurent  in  his  researches  obtained  a  body  from  naphthaline 
called  carminaphtha.  This  product  is  now  claiming  the  attention 
of  manufacturers,  and  is  said  to  produce  very  fine  shades  of 
colour  upon  fabrics. 

Before  making  any  further  remarks  upon  the  coal-tar  colours, 
I  wish  to  draw  your  attention  to  some  of  their  applications  to 
the  arts. 

I  have  told  you  that  most  of  the  coal-tar  colours  contain 
carbon,  hydrogen,  and  nitrogen,  and  that  they  are  generally 
organic  bases.  They  differ  essentially  from  most  of  the  vegetable 
colouring  matters,  which  contain,  with  but  few  exceptions,  only 
carbon,  hydrogen,  and  oxygen,  and  are  weak  acids.  You  will 
thus  understand  that  many  difficulties  had  to  be  encountered  in 
their  application  for  dyeing  and  printing,  because  they  would  not 
combine  with  the  ordinary  mordants  used  for  the  colouring 
matters  of  woods,  such  as  alumina  and  oxide  of  tin.  These 
observations  refer  to  the  dyeing  and  printing  of  vegetable  fibres, 
and  not  to  silk  or  wool,  as  these  materials  absorb  the  coal-tar 
colours  without  the  intervention  of  a  mordant. 

In  silk-dyeing,  the  principal  difficulty  experienced  in  applying 
the  coal-tar  colours  was  due  to  their  great  affinity  for  the  fibre, 
thus  preventing  the  dyer  from  obtaining  an  even  colour,  especially 
when  dyeing  light  shades.  After  a  time,  however,  it  was  found 
that  this  obstacle  could  be  overcome  by  dyeing  the  silk  in  a  weak 


38  THE   BRITISH   COAL-TAR   INDUSTRY 

soap  lather,  to  which  the  colour  had  been  added.  This  not  only 
caused  the  dyeing  to  proceed  with  less  rapidity,  but  also  kept  the 
surface  of  the  silk  in  good  condition.  Silk  dyed  by  this  process 
is  left  soft,  but  may  afterwards  be  rendered  hard  or  "  scroop  "  by 
rinsing  in  a  bath  of  slightly  acidulated  water. 

This  process  was  first  used  for  dyeing  silk  with  the  mauve 
or  aniline  purple.  It  has,  however,  been  since  found  suitable  for 
nearly  all  the  aniline  colours,  such  as  magenta,  Hofmann  and 
Britannia  violets,  etc.  For  dyeing  silk  with  coal-tar  colours  of 
an  acid  nature,  such  as  picric  acid,  dinitronaphthol,  etc.,  the  silk 
is  simply  worked  in  a  cold  aqueous  solution  of  the  colouring 
matter,  sometimes  slightly  acidulated,  as  when  using  the  sulpho 
acids  of  aniline  blue  or  soluble  blue.  The  process  of  printing 
silk  with  aniline  colours  is  comparatively  simple.  An  aqueous 
or  alcoholic  solution  of  the  colouring  matter  is  thickened  with 
gum  Senegal,  printed  on  with  blocks,  and,  when  dry,  exposed  to 
the  action  of  steam  for  about  half  an  hour.  The  gum  is  then 
washed  off,  and  the  goods  finished. 

Earlier  in  my  lecture  I  referred  to  the  formation  of  two 
colourless  products  from  magenta,  the  one  called  leucaniline, 
and  the  other  hydrocyanrosaniline. 

Some  few  years  since,  it  was  found  that  if  silk  dyed  with 
magenta  has  the  reagents  necessary  for  the  formation  of  these 
colourless  products  printed  upon  it,  what  is  called  a  discharge 
style  can  be  produced.  One  of  the  substances  used  for  effecting 
this  change  is  powdered  zinc  mixed  with  gum.  This  process 
also  applies  to  all  the  coloured  derivatives  of  magenta,  and  yields 
better  results  than  can  be  obtained  by  printing  on  the  colouring 
matter  and  leaving  the  white  parts,  because  the  colours  are 
always  clearer  when  dyed  than  when  printed.  But  this  is  not  all. 
When  printing  two  colours  on  silk,  say  a  pattern  with  a  green 
ground  and  purple  spots,  two  blocks  have  to  be  used,  the  one 
for  the  ground  and  the  other  for  the  spots  ;  and,  when  re- 
moving the  first  block,  the  silk  often  moves  slightly,  therefore 
when  the  spots  are  put  in  by  the  second  block  they  do  not 
exactly  register,  and  thus  an  imperfect  result  is  obtained. 
This  difficulty,  however,  can  be  avoided  by  taking  silk  dyed 
with  any  of  the  derivatives  of  magenta,  and  printing  it  with 
the  discharge  previously  mixed  with  the  colour  it  is  desired 
to  introduce,  of  course  employing  a  colouring  matter  which  is 
not  affected  by  the  discharge,  such  as  aniline  purple,  aniline 


THE   ANILINE   OR   COAL-TAR   COLOURS       39 

pink,  etc.  This  discharge  style  has  only  been  employed  for  silk 
at  present. 

We  will  now  turn  our  attention  to  the  methods  of  dyeing 
wool.  These  methods,  as  a  rule,  are  very  simple,  the  wool  being 
merely  worked  in  a  hot  aqueous  solution  of  the  desired  colouring 
matter,  no  mordant  being  required.  Acids  are  generally  found 
to  be  injurious,  a  neutral  bath  being  preferred,  and  the  operation 
finished  by  bringing  the  temperature  nearly  up  to  that  of  boiling 
water. 

With  the  blue  known  as  Nicholson's  blue,  the  process  of 
dyeing  is  different  from  that  just  given,  and  consists  of  two 
distinct  operations,  the  wool  being  first  worked  in  an  alkaline 
solution  of  the  colour,  which  gives  it  a  kind  of  grey  or  slate 
shade,  and  then  in  an  acid  bath,  which  develops  the  colour. 

The  printing  of  wool  is  similar  to  that  of  silk,  the  colouring 
matter  being  simply  thickened  with  gum,  printed  on  the  goods, 
steamed,  and  then  washed. 

The  dyeing  of  cotton  with  aniline  purple  at  first  presented 
many  difficulties.  This  colouring  matter  was  found  to  be  capable 
of  producing  a  very  beautiful  colour  without  a  mordant,  and  it 
was  proposed  to  employ  it  in  this  manner,  but  the  colour  thus 
obtained  would  not  bear  washing,  being  nearly  all  removed  with 
hot  water  and  soap.  Mordants,  such  as  alum,  were  then  ex- 
perimented with,  but  these  gave  no  results.  After  some  time 
Mr  R.  Pullar  and  myself  found  a  method  of  applying  this 
colouring  matter  to  cotton,  which  is  based  upon  the  insolubility 
of  the  compounds  it  forms  with  tannin.  In  using  this  process 
the  cotton  is  first  soaked  in  a  decoction  of  sumac  or  some 
other  tannin  agent,  then  in  a  solution  of  stannate  of  soda,  and, 
lastly,  in  water  slightly  acidulated  with  sulphuric  acid.  The 
cotton  thus  prepared  contains  an  insoluble  compound  of  tin  and 
tannin,  which  possesses  a  great  affinity  for  aniline  purple.  The 
stannate  of  soda  may  be  replaced  by  alum,  or  a  solution  of  tin 
salt.  This  method  of  preparing  cotton  has  been  found  suitable 
for  nearly  all  the  aniline  colours  discovered  since  the  mauve,  and 
is  now  almost  universally  employed  in  Great  Britain  for  cotton- 
dyeing.  Other  processes  have  been  proposed  for  cotton-dyeing, 
but  are  not  so  generally  employed  as  the  one  just  described. 

We  now  pass  on  to  the  application  of  coal-tar  colours  to  the 
art  of  calico-printing.  The  mauve,  when  first  introduced,  was 
applied  to  printing  in  a  very  simple  manner  ;  the  colouring 


40  THE   BRITISH   COAL-TAR   INDUSTRY 

matter  was  merely  mixed  with  gum  and  albumen,  printed  on  the 
goods  and  steamed  ;  by  this  process  the  albumen  became  in- 
soluble, and  fixed  the  colour.  Caseine  and  gluten  were  some- 
times used  as  substitutes  for  albumen.  Being  dissatisfied  with 
this  mechanical  mode  of  applying  aniline  purple,  in  conjunction 
with  Mr  Grey  I  made  a  number  of  experiments  with  a  view  of 
obtaining  some  more  chemical  method  of  fixing  this  colouring 
matter,  and  at  last  succeeded.  The  process  proposed  consisted 
in  printing  the  pattern  with  a  salt  of  lead,  then  converting  this 
into  the  oxide  or  a  basic  salt,  by  passing  the  goods  through  an 
alkaline  solution.  Thus  prepared,  they  were  worked  in  a  boiling 
solution  of  aniline  purple  in  soap.  In  this  way  a  very  pure 
colour  was  obtained  on  the  mordanted  parts,  the  soap  keeping 
the  whites  pure.  This  process,  however,  was  of  very  limited 
application,  as  it  could  only  be  applied  for  single-colour  patterns. 
After  this,  several  processes  were  patented  for  the  use  of  tannin 
for  fixing  the  mauve  ;  these  were  based  upon  the  method  of 
dyeing  cotton  previously  mentioned,  and  some  very  fast  results 
were  obtained  ;  but  as  these  methods  are  now  out  of  use,  I  will 
not  describe  them  further. 

The  process  now  nearly  universally  employed  in  the  north 
was  discovered  by  M.  Alexander  Schultz  and  myself  ;  it  consists 
in  printing  the  colouring  matter  with  a  mordant  composed  of 
a  solution  of  arsenite  of  alumina  in  acetate  of  alumina.  On 
steaming  the  cloth  printed  with  this  mixture  for  about  half  an 
hour,  the  colour  is  firmly  fixed  in  the  fibre.  After  steaming, 
the  goods  are  generally  soaped,  and  then  finished.  One  of  the 
great  advantages  of  this  process  is  that  it  can  be  worked  in 
patterns  with  a  great  variety  of  colours,  and  is  also  suitable  for 
nearly  all  the  aniline  colours,  as  well  as  the  mauve,  yielding 
shades  of  great  brilliancy. 

During  the  last  few  years,  much  attention  has  been  given 
to  the  application  of  aniline  black  in  calico-printing.  This 
substance  is  not  prepared  in  the  separate  condition,  but  formed 
on  the  fabric  ;  it  is  produced  by  printing  a  mixture  of  a  salt  of 
aniline,  chlorate  of  potassium,  and  sulphide  of  copper,  thickened 
with  starch,  upon  the  goods,  and  in  this  manner  a  dull  grey 
impression  is  obtained  ;  but,  after  three  or  four  days'  ageing, 
this  changes  to  a  dark  olive,  and  is  then  rendered  perfectly  black 
by  passing  the  goods  through  a  dilute  solution  of  carbonate 
of  soda.  This  colour  is  very  fast,  but  is  inclined  to  acquire  a 


THE   ANILINE   OR   COAL-TAR   COLOURS       41 

slightly  green  shade  by  long  exposure  to  the  air.  Unfortunately, 
it  cannot  be  printed  on  with  other  colours,  because  when  steamed 
the  cotton  is  destroyed  by  the  acid  character  of  the  mixture 
employed  for  its  formation.  It  can,  however,  be  printed  on  at 
the  same  time  as  madder  mordants,  and  these  can  be  afterwards 
dyed  with  a  lead  mordant,  so  that  when  passed  through  bi- 
chromate of  potassium  a  pattern  with  black  and  yellow  or  orange 
can  be  obtained. 

The  aniline  colours  have  produced  quite  a  revolution  in  the 
arts  of  dyeing  and  printing,  and  have  made  these  processes  far 
simpler  than  they  were,  and  there  is  such  a  variety  of  shades  of 
colour  now  sent  into  the  market  that  the  dyer  or  printer  has 
little  else  to  consider  than  the  intensity  of  the  colour  required  ; 
and,  in  fact,  if  a  dyer  has  a  large  order  to  execute  of  a  particular 
shade  of  colour  not  in  the  market,  he  will  not  trouble  about 
matching  it  himself,  but  sends  to  the  colour  manufacturer  to 
supply  him  with  a  product  capable  of  yielding  the  required  shade. 

Besides  dyeing  and  calico-printing,  several  other  branches 
of  industry  have  benefited  by  the  coal-tar  colours,  such  as  the 
arts  of  lithography,  type-printing,  paper  staining  and  colouring, 
etc.  Before  they  could,  however,  be  used  for  these  various 
purposes,  it  was  necessary  that  they  should  be  made  into  lakes 
or  pigments,  by  union  with  alumina  or  other  suitable  base  ;  but 
as  most  of  the  aniline  colours  are  of  a  basic  nature,  it  was  found 
impossible  to  combine  them  directly  with  a  metallic  oxide  like 
alumina  ;  advantage  was,  therefore,  taken  of  their  affinity  for 
starch  granules,  and  some  very  brilliant  products  were  obtained 
by  dyeing  powdered  starch  with  the  cold  aqueous  solution  of 
these  colouring  matters.  These  starch  powders,  however,  are 
wanting  in  covering  power  or  body,  so  that  other  processes  had 
to  be  sought  for,  and  now  these  lakes  are  made  upon  an  alumina 
base,  by  the  intervention  of  tannin  or  benzoic  acid. 

Many  attempts  have  been  made  to  prepare  a  pigment  from 
rosolic  acid  or  aurine,  and  this,  to  some  extent,  has  been  accom- 
plished by  precipitating  a  solution  of  the  colouring  matter  with 
alumina  ;  by  this  process,  a  bright  orange-scarlet-coloured  pro- 
duct can  be  obtained  ;  it  is,  however,  only  suitable  for  paper- 
staining.  I  have,  therefore,  lately  been  further  experimenting 
in  this  direction,  and  have  succeeded  in  forming  a  very  brilliant 
scarlet  pigment,  which  can  be  used  for  printing-inks  and  a 
variety  of  other  purposes. 


42  THE   BRITISH   COAL-TAR   INDUSTRY 

Upon  the  table  there  are  some  specimens  of  magenta, 
Britannia  violet,  aniline  blue,  green  and  orange  lakes,  and  also 
some  very  beautiful  and  intense-coloured  preparations  of  coal- 
tar  colours,  now  generally  called  carmines.  These  lakes,  when 
ground  with  printers'  varnish,  produce  printing-inks  of  very 
great  brilliancy,  and  are  extensively  used  for  this  purpose  ;  and 
Mr  Hanhart,  whose  name  is  so  intimately  connected  with  the 
art  of  lithography,  has  most  kindly  furnished  me  with  the  various 
illustrations  of  the  application  of  these  products  to  lithographic 
printing  for  this  lecture. 

These  lakes  in  a  wet  condition  are  being  largely  used  for 
paper-staining,  and  also  for  paper-colouring,  as  well  as  for  a 
variety  of  other  less  important  purposes. 

The  peculiar  bronze  surface  produced  by  evaporating  a 
solution  of  an  aniline  colour  has  been  taken  advantage  of  by  the 
manufacturer  ;  and  all  the  bronze  bonnets,  hats,  flowers,  and 
feathers,  so  much  worn  in  the  autumn  of  last  year,  derived  their 
lustre  from  aniline  colours.  When  first  employed  for  this 
purpose,  no  fixing  agent  was  used  with  them  ;  and  as  they  are 
mostly  soluble  in  water,  a  shower  of  rain  was  often  found  to 
cause  beautiful  purple  drops  to  fall  from  these  bronzed  bonnets 
and  hats,  and  produce  a  kind  of  mottled  pattern  upon  the  white 
collars,  and  sometimes  even  upon  the  face,  of  the  wearer. 

Aniline  colours  are  used  for  writing-inks,  colouring  soap, 
etc.  ;  but  as  these  applications  are  only  of  small  importance  from 
a  commercial  point  of  view,  I  will  not  spend  time  in  speaking 
about  them. 

I  have  in  this  lecture  brought  before  you  in  a  rapid — I  fear 
too  rapid — manner  an  account  of  most  of  the  coal-tar  colours  ; 
but,  before  concluding,  I  should  like  to  show  you  the  close 
relationship  which  exists  between  some  of  them,  especially 
between  those  derived  from  rosaniline  or  magenta. 

I  have  endeavoured  to  show  you  that  the  derivatives  of 
magenta  closely  agree  in  properties,  all  of  them  containing 
colourless  organic  bases,  the  colour  being  developed  upon  their 
combining  with  acids.  But  I  now  wish  to  show  you  more 
than  this,  by  briefly  explaining  their  chemical  structure.  To 
describe  this  thoroughly  it  would  be  necessary  for  me  to  enter 
fully  into  the  chemical  theory  of  substitution  ;  but  as  this  would 
occupy  a  great  deal  of  time,  I  must  content  myself  with  just 
mentioning  a  few  facts  connected  with  that  subject. 


THE   ANILINE   OR   COAL-TAR   COLOURS       43 

Rosaniline  and  its  derivatives  contain  carbon,  hydrogen,  and 
nitrogen,  as  I  have  told  you  on  a  previous  occasion.  Chemical 
substances  containing  hydrogen  often  hold  it  in  what  is  termed 
a  replaceable  condition,  that  is,  in  such  a  condition  that  it  may 
easily  be  removed  and  another  substance  of  equal  value  (either 
simple  or  compound)  introduced  in  its  place.  A  compound 
substance,  capable  of  replacing  hydrogen,  is  called  a  "  radical," 
and  I  want  to  speak  about  two  of  these  radicals,  one  called  ethyl, 
and  contained  in  iodide  of  ethyl,  the  other  called  phenyl,  and 
contained  in  aniline. 

Ethyl    contains  C2H5. 

Phenyl        „        C6H5. 

I  will  first  mention  a  familiar  instance  of  the  replacement  of 
hydrogen  by  a  radical.  Water  is  composed  of  two  equivalents 
of  hydrogen  and  one  of  oxygen,  thus  : 


Hio 

H/a 


Now,  it  is  quite  easy  to  remove  an  equivalent  of  this  hydrogen 
and  replace  it  by  ethyl  : 

H 


This  is  water  with  hydrogen  replaced  by  ethyl,  a  replacement 
compound  by  some  very  much  preferred  to  water  itself  ;  it  is 
alcohol. 

Rosaniline  contains  three  equivalents  of  hydrogen,  replace*- 
able  by  radicals.  This  is  the  formula  of  the  hydrochlorate  of 
rosaniline,  the  three  separate  H's  being  replaceable  : 

(C20H16) 

H 

H 

Now,  what  takes  place  upon  boiling  this  salt  with  aniline  ? 
The  phenyl  of  the  aniline  simply  takes  the  place  of  the  replaceable 
hydrogen,  producing  what  is  called  triphenylrosaniline.  The 
result  of  this  replacement  is  that  the  rosaniline  salt  has  been 
changed  from  red  into  blue  —  the  bleu  de  Lyon  —  which  is 
represented  thus  : 


44  THE   BRITISH   COAL-TAR   INDUSTRY 

Dr  Hofmann,  on  observing  this  relationship,  was  induced  to 
try  whether  he  could  replace  the  hydrogen  in  rosaniline  by  other 
radicals  than  phenyl.  He  tried  to  introduce  ethyl  by  digesting 
rosaniline  with  iodide  of  ethyl,  and  succeeded  in  introducing 
three  molecules  of  the  radical  ethyl  in  the  place  of  the  three 
replaceable  hydrogens.  I  will  endeavour  to  show  you  how  this 
takes  place,  by  the  following  equation  :  — 

(C2H5)I  (C2oH16M  HI 

(C2H5)I     +  \NyHCl.     =     HI 


IT  ft  \  T  T-TT  2        5 

(C2H5)I  (C2H5) 


Three  molecules  of  Hydrochlorate         Three  of  iodide  of      Hydrochlorate  of 

iodide  of  ethyl.  of  rosaniline.  hydrogen  or          triethylrosaniline. 

hydriodic  acid. 

Here  we  see  the  iodine  has  simply  exchanged  its  ethyl  for 
the  replaceable  hydrogen  of  rosaniline,  and  the  result  is  a  blue 
shade  of  the  Hofmann  violet. 

Now,  it  is  not  necessary  to  replace  the  three  hydrogens  ;  two 
may  be  replaced,  and  we  get  a  less  blue  violet.  Represented 
thus  : 


H 


Hydrochlorate  of 
diethylrosaniline. 

Or  one  may  be  replaced,  and  we  get  a  red  violet.     Represented 
thus  : 

(C2oH16) 

(C2 


Hydrochlorate  of 
ethylrosaniline. 

When  speaking  of  the  violet  imperial,  I  mentioned  that  it 
consisted  of  products  intermediate  between  rosaniline  and  the 
bleu  de  Lyon.  These  intermediate  substances  consist  of  ros- 
aniline with  one  or  two  equivalents  of  hydrogen  replaced  by 
phenyl. 

Up  to  the  present  moment  it  has  only  been  found  possible 
to  replace  one  equivalent  of  hydrogen  in  mauveine,  or  the  mauve 
dye,  and,  as  I  previously  mentioned,  it  is  curious  that  the  result 


THE   ANILINE   OR   COAL-TAR   COLOURS       45 

of  this  replacement  is  perfectly  opposite  to  that  which  takes 
place  in  the  case  of  rosaniline,  the  replacement  of  hydrogen  by 
ethyl  in  rosaniline  causing  it  to  become  bluer  in  shade,  and  the 
replacement  of  hydrogen  by  ethyl  in  mauveine  causing  it  to 
become  redder  in  shade.  The  following  is  the  formula  of  the 
hydrochlorate  of  ethyl-mauveine  or  dahlia  : 


But  although  I  have  tried  to  explain  the  relationship  of  these 
colouring  matters  as  simply  as  I  can,  yet  this  part  of  my  lecture 
assumes  much  of  the  character  of  a  lecture  on  theoretical 
chemistry.  Here  we  are  talking  about  substitution  products 
of  bodies,  a  branch  of  the  highest  theoretical  chemistry,  and  it 
must  strike  us  as  remarkable  when  we  find  that  these  considera- 
tions have  been  pressed  upon  us  by  the  discussion  of  bodies 
which  may  now  be  said  to  be  common  dyestuffs.  We  have 
also  been  talking  in  quite  a  familiar  manner  about  nitrobenzol, 
aniline,  iodide  of  ethyl,  aldehyd,  etc.,  substances  which  were, 
only  a  few  years  since,  the  recherche  compounds  of  the  laboratory. 
In  fact,  the  coal-tar  colour  industry  is  entirely  the  fruit  of  theo- 
retical chemistry.  Let  us  consider  the  enormous  rapidity  with 
which  this  industry  has  developed.  It  only  dates  from  1856, 
and  now  (in  1868)  we  have  large  factories  for  the  production 
of  coal-tar  colours,  not  only  in  Great  Britain,  but  in  Germany, 
France,  Switzerland,  America,  and  other  countries.  I  had  hoped 
to  have  been  able  to  give  you  a  statistical  account  of  this  industry, 
but  have  not  had  sufficient  time  for  this  purpose.  Dr  Hofmann, 
however,  in  his  report  on  the  coal-tar  colours  shown  at  the  Paris 
Exhibition  of  1867,  remarks  that  "in  1862,  the  value  of  these 
manufactures  had  risen  from  nothing  to  10,000,000  francs, 
or  more  than  £400,000  sterling.  At  the  present  day  this  sum 
is  trebled,  which  would  make  it  about  one  million  and  a  quarter 
pounds  sterling,  although  the  products  are  much  cheaper  than 
they  were  before."  And,  now,  when  you  hear  of  these  results, 
do  not  forget  that  they  are  the  truly  practical  fruits  of  theoretical 
chemistry,  not  studied  for  the  purpose  of  producing  commercial 
products,  but  simply  for  its  own  sake. 


II. :    i87o 

THE   ARTIFICIAL    PRODUCTION    OF 
ALIZARINE 

BY  PROFESSOR  H.  E.  ROSCOE,  F.R.S. 
(Discourse  delivered  at  the  Royal  Institution,  ist  April  1870) 

THE  discovery  of  artificial  alizarine,  whether  we  regard  its 
scientific  interest  or  its  practical  and  commercial  value,  is  of 
the  highest  importance,  and  marks  an  era  in  the  history  of  the 
application  of  chemistry  to  the  arts  and  manufactures  even 
of  greater  importance  than  the  memorable  discovery  made  by 
Mr  Per  kin  in  1856  of  the  production  of  aniline  violet,  or 
mauve. 

Since  the  above-named  year  great  progress  has  been  made  in 
the  theoretical  investigation  of  natural  and  artificial  colouring 
matters,  as  well  as  in  their  preparation  on  a  large  scale.  The 
chemistry  of  colouring  matters  has  now  taken  a  high  and  im- 
portant position,  and  chemists,  instead,  as  formerly  was  their 
wont,  of  getting  rid  of  all  colouring  matters  as  something  foreign 
to  their  objects  of  investigation,  have,  since  Mr  Perkin's  dis- 
covery, found  out  that  the  examination  of  colouring  matters  may 
not  only  lead  to  scientific  laurels,  but  may  sometimes  yield  fruit 
of  another  and  not  less  acceptable  kind. 

We  owe  to  the  brains  and  hands  of  two  German  chemists, 
Graebe  and  Liebermann,  this  remarkable  discovery,  which  differs 
from  all  the  former  results  which  have  been  brought  about  by 
the  application  of  science  to  the  chemistry  of  colouring  matters, 
inasmuch  as  this  has  reference  to  the  artificial  production  of  a 
natural  vegetable  colouring  substance  which  has  been  used  as  a 
dye  from  time  immemorial,  and  is  still  employed  in  enormous 
quantities  for  the  production  of  the  pink,  purple,  and  black 

46 


THE  ARTIFICIAL  PRODUCTION  OF  ALIZARINE   47 

colours  which  are  seen  everywhere  on  printed  calicoes,  viz. 
alizarine,  the  colouring  principle  of  madder. 

It  is  from  the  liquid  tarry  products  of  the  destructive  distilla- 
tion of  coal,  a  rich  source  of  interest  to  chemists,  that  we  now 
derive  this  new  colouring  matter. 

The  following  table  contains  the  results  of  experiments  made 
on  a  large  scale,  indicating  the  various  yields  of  tar  from 
different  qualities  of  coal  distilled  in  the  gasworks  of  various 
towns  : — 

DESTRUCTIVE  DISTILLATION  OF  COAL 
100  tons  of  cannel  and  bituminous  coal  yield  the  following  products:— 


Gas. 

Tar. 

Ammonia 
water. 

Coke. 

I 

22-25 

8-50 

9'5° 

5975 

Average    of    many 

experiments. 

2 

20*01 

7-85 

7-14 

65*00 

Manchester. 

1 

2O'4O 

6-4 

5-4 

67-85 

Dukinfield. 

4 

21'7 

7'5 

5'8 

65*0 

Macclesfield. 

5 

I6'3 

10-7 

8-0 

65*0 

Salford. 

From  a  careful  series  of  experiments  made  by  a  large  tar 
distiller  the  following  numbers  are  derived,  showing  the  average 
composition  of  gas  tar  : — 

ioo  tons  of  coal-tar  on  distillation  yield  : — 


I 

2 

Naphtha. 

Light  oils 
and  carbolic 
acid. 

Heavy  oils, 
naphthalene, 
anthracene. 

Pitch. 

Water,  gas, 
and  loss. 

3*o 
3'° 

i'S 

0-8 

35*° 
25-0 

5o*o 
60*0 

10-5 
12*2 

It  is  from  benzol,  C6H6,  discovered  by  Faraday  in  1825,  that 
the  aniline  colours  are  all  of  them  prepared.  The  colour-produc- 
ing powers  of  the  coal  products  are,  however,  yet  far  from  being 
exhausted.  It  is  by  means  of  another  and  hitherto  comparatively 
unknown  hydrocarbon,  anthracene,  C^Hjo,  that  the  newest 


48  THE   BRITISH   COAL-TAR   INDUSTRY 

triumphs  of  the  chemist  have  been  won.  This  is  a  substance 
which  in  the  pure  state  few  chemists  have  seen  (1870),  and 
upon  which  only  two  or  three  had  previously  experimented  ;  and 
yet  by  one  happy  discovery — and  by  an  investigation  which  more 
than  almost  any  other  exhibits  the  value  of  the  synthetic  power 
of  modern  research — this  unknown  body  has  been  made  to  yield 
a  colouring  matter  of  the  greatest  possible  value.  The  truth  of 
this  will  at  once  be  evident  when  we  learn  that  the  total  growth 
of  madder  is  estimated  to  reach  47,500  tons  per  annum,  worth 
£45  per  ton,  and  having,  therefore,  a  value  of  ^2,150,000.  Of 
this  nearly  one-half  is  used  in  the  United  Kingdom,  so  that  no 
less  a  sum  than  j£  1,000,000  is  now  paid  by  us  for  madder  grown 
in  foreign  countries.  This  will  now,  in  part  at  least,  go  to 
benefit  our  own  population,  as  we  can  now  transform  our  coal 
into  this  invaluable  colouring  matter. 

In  an  experiment  made  on  a  large  scale  it  was  found  that 
100  tons  of  tar  yield  0*63  ton  of  anthracene,  or  i  ton  of 
anthracene  can  be  obtained  from  the  distillation  of  about 
2000  tons  of  coal,  not  reckoning  the  quantity  of  anthracene  con- 
tained in  the  pitch. 

Madder  is  the  root  of  several  species  of  Rubiay  amongst 
which  the  R.  tinctorium  is  the  most  valued  for  its  dyeing  properties. 
This  grows  in  Holland,  Asia  Minor,  and  in  the  south  of  France 
and  of  Russia.  A  species  native  to  England  is  the  R.  peregrina. 
This  belongs  to  the  order  Rubiace<e,  the  native  members  of  which, 
as  the  Galiums,  are  mostly  inconspicuous  wild  plants.  Some  of 
the  foreign  species  are,  on  the  contrary,  important  plants,  such  as 
the  cinchona,  ipecacuanha,  and  coffee  plants,  and  these  are  dis- 
tinguished for  the  number  and  variety  of  the  peculiar  principles 
which  they  yield,  as  quinine,  cinchonine,  caffeine,  alizarine. 
(Thanks  to  the  kindness  of  Dr  Schunck,  the  speaker  was  able  to 
show  a  young  madder  plant.) 

In  spite  of  the  many  investigations  of  madder  which  have 
been  made,  chemists  are  still  in  doubt  as  to  the  nature  of  many 
of  its  constituents.  Some  attribute  its  colouring  powers  to  the 
presence  of  at  least  two  substances — alizarine  and  purpurine  ; 
whilst  others  say  that  only  one  of  these  produces  the  true 
madder  colours. 

Alizarine  was  discovered  and  obtained  from  madder,  as  a 
crystalline  sublimate,  by  Robiquet  and  Colin  in  1831  ;  but  little 
importance  attached  to  this  discovery  until  Schunck,  in  1848, 


THE  ARTIFICIAL  PRODUCTION  OF  ALIZARINE   49 

showed  that  all  the  finest  madder  colours  contain  only  alizarine 
combined  with  bases  and  fatty  acids.  The  second  colouring 
matter,  termed  purpurine,  was  discovered  by  Persoz.  It  con- 
tributes to  the  full  and  fiery  red  colour  in  ordinary  madder  dye- 
ing, but  dyes  a  bad  purple,  alizarine  being  essential  to  the  latter. 
Purpurine  disappears  during  the  purifying  processes  of  soaping, 
etc.,  being  far  less  stable  than  alizarine.  It  is  distinguished  from 
alizarine  by  its  solubility  in  boiling  alum  liquor. 

These  two  colouring  principles  may  likewise  be  easily  dis- 
tinguished by  their  spectra,  alizarine  producing  a  set  of  dark 
absorption-bands,  quite  different  from  those  of  purpurine,  which 
again  vary  according  to  the  solvent.  Alizarine  can  be  obtained 
in  yellow  needle-shaped  crystals  by  simple  sublimation  from  the 
dried  madder  ;  but  this  colouring  matter  is,  singularly  enough, 
not  contained  ready  formed  in  the  fresh  madder  root,  but  is  the 
product  of  a  peculiar  decomposition.  For  a  proof  that  fresh 
madder  does  not  contain  alizarine  we  have  only  to  extract  the 
moist  root  with  alcohol,  when  neither  the  alcoholic  extract  nor 
the  insoluble  residue  will  be  found  to  possess  tinctorial  power. 
We  owe  this  knowledge  to  the  researches  of  Schunck  and 
Higgin,  who  have  proved  that  alizarine  is  produced  by  a 
peculiar  kind  of  fermentation  which  partly  occurs  in  the  root  on 
standing,  and  partly  takes  place  in  the  dyebeck,  when  the  powdered 
madder  is  treated  with  water.  A  crystalline  glucoside,  termed 
rubianic  acid  (Schunck),  is  contained  in  the  root,  and  it  is  this 
which  splits  up  simply  into  alizarine  and  glucose.  This  acid  crys- 
tallises in  fine  yellow  needles,  and  gives  a  definite  and  crystalline 
potash  salt,  from  which  it  was  shown  to  contain  twenty-six  atoms  of 
carbon  in  the  molecule.  Hence,  as  no  other  product  but  glucose 
is  formed,  it  follows  that  alizarine  must  contain  C2e — C12=C14. 
(This  decomposition  of  rubianic  acid  into  alizarine  was  shown  by 
boiling  with  an  acid,  and  adding  caustic  soda,  when  the  blue 
solution  of  alkaline  alizarate  was  seen.)  The  formation  of  ali- 
zarine in  extracts  of  madder  root  is  effected  by  a  ferment  peculiar 
to  the  plant  and  called  Erythrozym.  It  is  a  ferment  sui  generis, 
since  no  other  ferment  produces  the  same  effect.  When  mixed 
with  a  solution  of  rubian  or  rubianic  acid,  at  the  ordinary 
temperature,  the  latter  is  rapidly  decomposed  as  with  acids. 
This  is  what  takes  place  in  making  fleur  de  garance.  Dyers 
raise  the  temperature  of  their  madder-baths  gradually  up  to 
boiling-point,  because  the  application  of  a  high  temperature 

4 


50  THE   BRITISH   COAL-TAR   INDUSTRY 

destroys  the  ferment.  When  the  temperature  is  gradually  raised, 
the  ferment  acts  upon  the  glucoside,  and  produces  alizarine. 

That  the  colouring  matter  in  fresh  madder  root  is  not 
alizarine  can  be  easily  shown  by  rubbing  the  soft  portions  of 
the  root  on  to  paper,  when  a  yellow  stain  will  be  produced, 
which,  on  treatment  with  an  alkali,  shows  the  bright  red  colour 
of  an  alkaline  solution  of  rubian  instead  of  the  blue  solution 
of  alizarate. 

According  to  Schunck,  the  origin  of  purpurine,  and  its  relation 
to  alizarine,  are  still  involved  in  obscurity. 

The  hypothesis  which  of  late  years  has  done  more  than  any 
other  to  stimulate  experiment  and  enlarge  our  views  in  organic 
chemistry  is  undoubtedly  Kekule's  theory  of  the  tetrad  nature  of 
carbon  and  his  explanation  of  the  constitution  of  the  carbon 
compounds.  In  the  so-called  paraffine  group  of  organic  sub- 
stances, the  carbon  atoms  are  supposed  to  be  connected  together 
by  single  links  of  the  four  bonds  attached  to  each  atom,  thus 
giving  rise  to  saturated  compounds  by  the  attachment  of  other 
elements  or  radicals  to  the  free  bonds.  In  the  group  of  aromatic 
substances  with  which  we  are  specially  concerned  the  carbon 
atoms  are  more  closely  linked  together,  or,  in  other  words, 
fewer  atoms  of  hydrogen  are  necessary  to  saturate  an  aggrega- 
tion of  carbon  atoms  than  is  the  case  in  the  other  group.  We 
can  explain  this,  upon  the  assumption  of  the  tetrad  character 
of  carbon,  by  supposing  that  each  carbon  atom  is  attached  to 
its  neighbour  alternately  by  one  and  two  bonds. 

Another  singular  property  of  these  aromatic  bodies  is  that 
they  all  contain  at  least  six  atoms  of  carbon,  and  that  the  simplest 
hydrocarbon  of  which  they  are  made  up  is  benzol,  C6H6.  So 
that  we  may  regard  all  these  aromatic  compounds  as  benzol 
derivatives,  and  this  hydrocarbon  may  be  considered  as  the 
skeleton  round  which  many  complicated  substances  are  arranged. 
So  that  by  the  replacement  of  one  atom  of  hydrogen  by  (NH2) 
we  obtain  aniline,  or  by  (OH)  phenol,  etc.  From  the  knowledge 
gained  by  the  investigation  on  the  quinones,  Graebe  came  to 
the  conclusion  that  alizarine  belongs  to  the  quinone  series  ;  and, 
availing  themselves  of  Baeyer's  reaction,  by  which  phenol  can 
be  converted  into  its  hydrocarbon  benzol,  Graebe  and  Liebermann 
passed  the  vapour  of  natural  alizarine  obtained  from  madder 
over  heated  zinc-dust,  and  found  that  the  hydrocarbon  they 
formed  was  identical  in  all  its  properties  with  anthracene, 


THE  ARTIFICIAL  PRODUCTION  OF  ALIZARINE    51 

C14H10,  from  coal  tar.  Hence  they  confirmed  Schunck's  con- 
clusions that  the  molecule  of  alizarine  contained  fourteen  atoms 
of  carbon.  Having  thus  got  hold  of  the  backbone,  as  it  were, 
of  the  compound,  it  only  remained  for  them  to  clothe  the 
hydrocarbon  with  the  four  additional  atoms  of  oxygen,  and  to 
take  off  the  two  atoms  of  hydrogen  in  excess,  in  order  to  obtain 
alizarine. 

Laurent  and  also  Anderson  had,  many  years  ago,  obtained 
a  body  of  the  composition  C14H8O2,  and  Graebe  recognised  this 
as  the  quinone  of  anthracene  ;  and  he  now  only  required  to  re- 
place in  this  two  atoms  of  hydrogen  by  two  of  hydroxyl  (OH), 
in  order  to  obtain  alizarine,  which  clearly  appeared  to  be  a 
quinone  acid  — 


C14H10  C14H8(0")2  C14HOH 

(OH 

Anthracene  Anthraquinone  Alizarine. 

This  replacement  of  hydrogen  can  be  effected  by  bromine,  by 
which  bibromanthraquinone,  Ci4H6Br2O2,  is  formed,  and  this, 
on  fusion  with  caustic  potash,  gives  potassium  alizarate,  yielding 
pure  alizarine  on  treatment  with  hydrochloric  acid.  The  high 
price  of  bromine  rendered  this  process  unavailable  for  manu- 
facturing purposes,  and  hence  another  plan  was  simultaneously 
proposed  by  several  chemists  for  effecting  the  same  end  in  a 
cheaper  mode.  Use  was  hereby  made  of  Kekule's  and  Wurtz's 
reaction  in  the  formation  of  sulpho-benzoic  acid.  On  treating 
anthraquinone  with  strong  sulphuric  acid  to  a  high  temperature, 


the   di-sulpho   acid    C14H6O2-jgQ3TT    is   formed,  and   this,    on 

heating  with  concentrated  solution  of  potash,  yields  the  sulphite 
and  alizarate  of  potassium  ;  from  the  latter  substance  pure 
alizarine  is  obtained  by  the  action  of  acids. 

In  the  following  table  we  have  a  statement  of  the  synthetic 
production  of  alizarine  from  its  constituent  elements  : — 

SYNTHESIS  OF  ALIZARINE 

1 .  Acetylene  by  direct  union  of  carbon  and  hydrogen  in  electric  arc : 

C2  +  H2  =  C2H2.  (Berthelot,  1862.) 

2.  Benzol  (tri-acetylene)  from  acetylene  by  heat : 

C6H6.  (Berthelot,  1866.) 


52  THE   BRITISH   COAL-TAR   INDUSTRY 

3.  Anthracene  from  benzol  and  ethylene  : 


(Berthelot,  1866.) 

4.  Alizarine  from  anthracene  (Process  No.  i). 

(Graebe  and  Liebermann,  1869.) 

(A)  Oxyanthracene  or  anthraquinone  by  nitric  acid  : 

C14H6(OH)2.  (Anderson,  1861.) 

(B)  Bibromanthraquinone  by  action  of  bromine  : 

C14H8O2  +  2Br2  =  C14H6Br2O2  +  2BrH. 

(C)  Alizarine  by  action  of  caustic  potash  : 
C14H6Br202  +  4KHO  =  C14H6(OK)2O2  +  2KBr  +  2H2O. 

Potassium  alizarate. 

5.  Alizarine  from  anthracene  (Process  No.  2)  : 

(Graebe  and  Caro,  Perkin,  Schorlemmer  and  Dale.) 

(A)  Disulphoanthraquinonic  acid  from  anthraquinone  : 
C14H6(OH)2  +  2H2S04  =  CUH602         «        +  2H2O. 


(B)  Alizarine  from  the  above  by  the  action  of  potash  : 
C14H602      °         +  4KHO  -  C14H602 


Alizarine. 

Mr  Perkin  states  that  an  intermediate  substance  is  formed  in 
this  reaction  having  the  formula  C14H6(O)2"sOQO  ,  and  this, 


when  heated  with  potash,  splits  up  into  alizarine  and  a  sulphite. 
Other  yellow-coloured  products  are,  according  to  Perkin,  con- 
tained in  the  alizarine  as  sent  out  from  his  manufactory.  The 
nature  of  these  yellow  crystalline  bodies  is  as  yet  unknown. 

Of  the  identity  of  the  natural  with  the  artificial  alizarine 
there  can  be  no  doubt  ;  they  agree  in  all  their  physical  and 
chemical  properties.  Their  absorption-spectra  are  identical, 
their  tinctorial  powers  are  the  same  ;  the  coloured  lakes  which 
they  form  with  alumina,  iron,  and  copper  salts  are  of  the  same 
tint  and  possess  the  same  degree  of  solubility,  and  these  remain 
alike  unaltered  by  the  action  of  light,  so  that  when  they  are 
fixed  in  the  cotton-fibre  they  yield  equally  fast  colours. 

It  is  difficult  to  predict  how  far  the  artificial  alizarine  will 
in  future  restrict  the  growth  of  madder  ;  but  there  is  no  doubt 
that  for  many  styles  of  calico-printing  the  artificial  alizarine  is 
of  the  greatest  value,  and  we  may  naturally  expect  to  see  very 


THE  ARTIFICIAL  PRODUCTION  OF  ALIZARINE    53 

important  changes  effected  in  this  branch  of  chemical  industry 
in  the  further  practical  application  of  this  new  discovery. 

CONTRIBUTIONS  TO  THE  HISTORY  OF  ALIZARINE,  C14H8O4 

1825.  Faraday  discovered  benzol,  C6H6,  in  coal-gas  oil. 

1831.  Robiquet  and  Colin  discovered  alizarine  in  madder  root. 

1832.  Dumas  and  Laurent  discovered  anthracene  in  coal  oils. 
1848.  Schunck  gave  the  composition  of  alizarine,  C14H10O4. 
1850.  Strecker  gave  the  composition  of  alizarine,  C10H6O3. 
1862.  Anderson  examined  anthracene  compounds,  C14H10. 

1865.  Kekule  explained  the  constitution  of  the  aromatic  compounds. 

1866.  Baeyer  obtained  benzol  from  phenol. 
1868.  Graebe  investigated  the  quinones. 

1868.  Graebe  and  Liebermann  obtained  anthracene  from  alizarine. 

1869.  Graebe  and  Liebermann  obtained  alizarine  from  anthracene. 


III.:    1879 

THE    HISTORY    OF    ALIZARIN    AND    ALLIED 
COLOURING    MATTERS 

BY  W.  H.  PERKIN,  F.R.S. 

(Journal  of  the  Society  of  Art *,  1879,  p.  572) 

THIS  paper  gives  a  very  detailed  and  complete  account  of  the 
history  and  synthetic  production  of  alizarin.  The  main  points  are 
summarised  in  the  " Hofmann  Memorial  Lecture"  delivered  by  Dr 
Perkin  before  the  Chemical  Society  in  1896,  and  reprinted  in  the 
present  work  (see  p.  141). 

The  ground  covered  by  Perkin' s  1879 r  lecture  is  indicated  by  the 
following  headings : — 

History  and  Applications  of  Madder. 

Schunck's  Researches  on  "  Natural  Alizarin." 

Graebe  and  Liebermann's  Researches. 

Graebe  and  Liebermanns  First  Synthesis  ^Bromine  process). 

The  Sulphonic  Acid  Process  (Perkin^  Graebe  and  Liebermann, 

Caro). 

Impurities  in  Synthetic  Alizarin. 
Alizarin  Orange  and  Alizarin  Blue. 
The  History  of  the   Technical  Manufacture   of  Alizarin   in 

Perkins  works. 
The  Constitution  of  Alizarin. 

The  concluding  paragraphs  only  of  this  interesting  paper  are 
quoted  : — 

Having  now  given  an  account  of  the  manufacture  of  artificial 
alizarin,  it  will  be  interesting  to  inquire  into  the  commercial 
results  of  this  industry,  and,  firstly,  what  has  been  its  influence 
upon  the  sale  of  madder  and  its  derivatives.  I  mentioned  at  the 

54 


THE   HISTORY   OF   ALIZARIN 


55 


commencement  of  this  paper  that  the  annual  value  of  the  im- 
ports into  the  United  Kingdom,  of  madder  and  garancine,  from 
1859  to  1868,  amounted  to  about  £1,000,000  sterling,  with  prices 
averaging  for  madder  455.  to  505.  per  cwt.,  and  for  garancine, 
1505.  In  the  subjoined  table  will  be  seen  the  remarkable 
changes  that  have  taken  place  in  the  imports,  and  also  the  great 
reduction  in  price  : — 

AVERAGE  ANNUAL  IMPORTS  OF  MADDER  AND  GARANCINE 
INTO  THE  UNITED  KINGDOM 


Year. 

Madder. 

Garancine. 

French 
madder. 

Turkey 
roots. 

Garancine. 

cwts. 

cwts. 

1859) 
1868  j 

3°5>840 

45>56o 

45s. 

5os. 

1508. 

1875 

100,280 

25,860 

— 

— 

— 

1876 

59i*37 

I5>396) 

or      V 

— 



— 

6,436) 

1877 

38,711 

8,875 

— 

— 

— 

1878 

32,990 

2,79° 

1  8s. 

175. 

65s. 

Up  to  and  during  1876  considerable  quantities  of  artificial 
alizarin  were  imported  from  the  Continent,  and  entered  at  the 
Customs  as  garancine  or  madder,  and  this  having  been  brought 
to  the  notice  of  the  officials,  the  returns  made  subsequently  are 
more  reliable.  The  imports  of  garancine  were  returned  by  the 
Board  of  Trade  in  1876  as  15,396  cwts.  when  first  published, 
but  in  the  following  year,  when  the  figures  for  1876  were  given 
for  comparison  with  those  of  1877  and  1878,  the  returns  were 
stated  as  only  6436  cwts.  The  erroneous  entries  were  most 
probably  made  to  evade  the  penalties  for  the  infringement  of 
patent  rights.1 

Dutch  ground  madder  has  been  relatively  much  higher  in 
price  than  the  other  qualities.  This  is  owing  to  its  extensive 
use  in  wool  dyeing.  For  various  reasons  artificial  alizarin  has 
made  but  little  progress  in  its  application  to  wool  dyeing,  and 

1  A  method  so  often  resorted  to  as  to  render  English  chemical  patents 
nearly  useless  as  a  protection  against  infringements  by  foreign  manufacturers, 
the  results  of  this  being  alike  detrimental  to  the  inventor  and  injurious  to  the 
national  interests. 


56  THE   BRITISH   COAL-TAR   INDUSTRY 

Dutch  madder  being  mostly  used  for  this  purpose,  its  prices 
have  been  maintained  at  from  28s.  for  ordinary  "  Ombro "  to 
about  405.  to  455.  for  crop  madder.  The  wool  dyers  have, 
however,  been  working  cautiously  with  artificial  alizarin,  and 
now  some  of  them  are  using  it  somewhat  largely,  and  considering 
its  cheapness  as  compared  with  Dutch  madder,  no  doubt  they 
will  soon  find  how  to  use  it  successfully  and  cease  to  employ 
madder. 

The  decline  in  the  sale  of  madder  is  still  rapidly  going  on. 
During  the  first  two  months  of  last  year  the  imports  were — 

Madder 6846  cwts. 

Garancine 533     » 

During  the  first  two  months  of  this  year  they  were — 

Madder 2185  cwts. 

Garancine 175     „ 

or  about  two-thirds  less.  And  not  only  so,  but  the  price  is  still 
declining.  Turkey  roots  may  now  be  bought  at  us.  per  cwt., 
whereas  before  artificial  alizarin  was  introduced  they  were  sold, 
on  an  average,  at  505.  At  the  present  prices  of  madder,  its 
cultivation  is  unremunerative,  and  will,  undoubtedly,  be  soon  a 
thing  of  the  past.  Such  has  been  the  success  of  artificial  alizarin 
in  competing  with  madder  and  garancine  in  this  country,  and  it 
is  equally  true  of  other  countries.  The  quantity  of  madder 
grown  in  all  the  madder-growing  countries  of  the  world  prior  to 
1868  is  estimated  at  about  70,000  tons  per  annum.  The  amount 
of  artificial  alizarin  now  produced  is  equal  in  dyeing  power  to 
considerably  more  than  this  ;  in  fact,  the  lowest  estimate  I  have 
been  able  to  get  for  1878,  and  which  was  confirmed  from  other 
sources,  is  9500  tons,  which  is  equivalent  to  950,000  tons  of 
madder.  This  remarkable  result  has  been  arrived  at  in  ten 
years  only. 

To  produce  this  quantity  of  artificial  alizarin,  there  are  about 
nine  manufacturers  on  the  Continent,  and  one  in  this  country, 
Messrs  Burt,  Bolton  &  Haywood,  who  have  two  large  works 
for  its  production,  viz.  the  original  works  at  Greenford  Green, 
and  new  ones  at  Silvertown. 

Graebe  and  Liebermann,  in  their  paper  in  the  Moniteur 
Scientifique?-  give  some  statistics  of  the  production  of  artificial 

1  Moniteur  Scientifique,  April  1879,  416. 


THE   HISTORY   OF   ALIZARIN 


57 


alizarin  which,  however,  require  correcting.  They  also  leave 
out  the  years  1869  and  1870.  In  1869  we  had  advanced  in  the 
manufacture  so  far  as  to  send  colour  into  the  market,  the  first 
invoice  being  dated  October  4th,  and  that  year  we  produced 
about  one  ton.  In  1870  we  produced  40  tons  ;  in  1871,  220 
tons  ;  in  1872,  300  tons  ;  and  in  1873,  435  tons.  Up  to  the 
end  of  1870  we  were  practically  the  only  makers  of  this  product, 
one  of  the  largest  chemical  and  coal-tar  colour  manufacturing 
firms  of  Germany,  with  whom  we  were  in  correspondence,  stating 
that  in  November  1870  they  had  only  lately  commenced  pro- 
ducing 50  Ibs.  of  alizarin,  10  per  cent,  quality,  per  day,  and  that 
no  one  else  in  that  country  was  supplying  artificial  alizarin  ;  and 
in  1871  we  were  practically  the  only  producers  of  quantity,  at 
any  rate  during  the  first  part  of  the  year,  for  in  March  1871 
the  firm  already  referred  to,  and  who  had  great  opportunities  of 
knowing  what  was  being  done  in  their  country,  wrote  that  they 
had  not  received  knowledge  of  any  establishment  but  their  own 
manufacturing  artificial  alizarin. 

In  November  1871,  however,  Messrs  Gessert  Fr&res 
announced  to  the  Industrial  Society  of  Mulhouse  that  they  had 
produced  30,792  kilogrammes  of  alizarin  in  paste.  This  is 
equal  to  about  30  tons,  an  amount  which  was  evidently  con- 
sidered by  them  a  very  large  quantity.1 

Graebe  and  Liebermann's  statistics  are  as  follows  compared 
with  our  production  : — 

Graebe  and  Perkin  &  Sons' 


1869 
1870 
1871 

1872 
1873 


Liebermann.  productions. 

Tons.  Tons. 

I 

40 

125-  150  220 

4OO-  5OO  300 


900-1000       435 

Without  wishing  to  detract  from  Graebe  and  Liebermann's 
original  discovery,  we  may  say,  that  the  birthplace  of  the  manu- 
facture of  artificial  alizarin  was  in  England.  It  was  in  this 
country  that  the  difficulties  and  doubts  about  the  manufacture 
and  supply  of  the  raw  material,  anthracene,  were  solved,  and 
the  production  of  artificial  alizarin  by  new  processes  success- 
fully accomplished.  After  these  results  were  obtained  in  this 
country,  Continental  chemists  were  encouraged  to  manufacture 

1  Moniteur  Scientifique^  April  1879,  416. 


5 8  THE  BRITISH   COAL-TAR   INDUSTRY 

on  a  comparatively  large  scale,  but  up  to  the  end  of  1873  the 
English  manufacturers  had  practically  no  competition  in  the 
home  market. 

Having  considered  the  amount  of  artificial  alizarin  now  manu- 
factured, it  will  be  of  interest  to  see  what  its  money  value  is. 

Taking  the  lowest  estimate,  viz.  9500  tons,  and  calculating 
its  selling  prices  at  £150  per  ton,  the  annual  value  amounts  to 
no  less  than  £1,425,000,  or  nearly  a  million  and  a  half. 

As  a  dye,  it  is  now  at  most  not  more  than  one-third  of  the 
average  price  of  madder  in  1859—1868.  Consequently,  in  the 
United  Kingdom,  when  the  annual  value  of  madder  imported 
was  £1,000,000,  the  annual  saving  is  very  great. 

While  collecting  the  statistics  about  alizarin,  I  thought  it 
would  be  of  interest  to  get,  if  possible,  the  statistics  of  the  entire 
coal-tar  colour  industry,  and  to  the  kindness  of  H.  Caro,  of  the 
Badische  Anilin  und  Soda  Fabrik,  I  am  indebted  for  most  of 
the  following  particulars  : — 

ESTIMATED  VALUE  OF  THE  PRODUCTION  OF  COAL-TAR 
COLOURS  IN  1878 

Germany  .  .  ^2,000,000,  of  which  four-fifths  are  exported. 

England  .  .            450,000 

France  .  .  .            350,000 

Switzerland"  .  .            350,000 

Total  .         .     .£3,150,000 

In  referring  to  the  works  which  have  been  set  up  for  the 
purpose  of  making  coal-tar  colours,  I  thought  it  would  be  of 
interest  to  show  a  copy  of  a  rough  sketch  of  the  first  works 
erected  for  this  purpose  as  they  appeared  in  1868,  two  years 
after  the  patent  for  the  mauve  was  taken  out. 

These  works  were  not  one  year  old  when  sketched,  and  the 
practicability  of  making  the  mauve  commercially  had  only  been 
proved  a  short  time.  In  1873  they  had  increased  to  such  an 
extent  as  to  cover  about  six  acres.  They  are  represented  at  this 
date  by  a  copy  of  a  photograph.1 

There  are  now  in  this  country  six  coal-tar  colour  works  ;  in 
Germany,  no  less  than  seventeen  ;  in  France,  about  five  ;  and  in 

1  A  copy  of  a  photograph  of  the  works  as  they  appeared  in  1873,  and  a 
facsimile  of  the  sketch  referred  to  in  the  text,  showing  the  works  in  1858,  is 
given  in  a  lithograph  issued  as  a  supplement  to  the  Journal  of  the  Society  of 
Arts,  May  3oth,  1879. 


THE   HISTORY   OF   ALIZARIN  59 

Switzerland,  four.  There  are  also  three  works  in  Germany  and 
three  in  France  which  manufacture  aniline  in  enormous  quantities 
for  the  production  of  coal-tar  colours. 

Such  is  the  wonderful  growth  of  this  industry,  which  dates 
only  from  1856.  It  is  the  fruit  of  scientific  researches  in  organic 
chemistry,  conducted,  mostly,  from  a  scientific  point  of  view  ; 
and,  while  this  industry  has  made  such  great  progress,  it  has,  in 
its  turn,  acted  as  a  handmaid  to  chemical  science,  by  placing  at 
the  disposal  of  chemists  products  which  otherwise  could  not  have 
been  obtained,  and  thus  an  amount  of  research  has  been  con- 
ducted through  it  so  extensive  that  it  is  difficult  to  realise,  and 
this  may,  before  long,  produce  practical  fruit  to  an  extent  we 
have  no  conception  of.  One  very  important  colouring  matter 
related  to  coal  tar,  and  one  of  the  original  sources  of  aniline — a 
product  of  as  great  importance  as  alizarin — has  yet  to  be  pro- 
duced on  the  large  scale.  I  refer  to  indigo.  Baeyer  has  shown 
that  it  can  be  produced  artificially,  but  at  present  no  practical 
means  of  accomplishing  it  have  been  discovered.  No  doubt, 
however,  it  will  not  be  many  years  before  this  is  achieved,  and 
the  cultivation  of  the  indigo  plant  shares  the  fate  of  madder. 

The  Chairman,  Prof.  F.  A.  ABEL,  C.B.,  F.R.S.,  said  Mr 
Perkin  had  dwelt  with  very  justifiable  pride  on  the  fact  that 
England  had  been  the  birthplace  of  this  particular  branch  of 
industry  connected  with  the  coal-tar  colours,  of  which  he  had 
given  the  history  in  so  lucid  a  manner.  He  had  not,  however, 
recalled  to  their  minds  that  which  was  also  true,  that  England 
was  also  the  birthplace  of  the  entire  coal-tar  industry,  the 
development  of  which  he  had  so  graphically  and  clearly  narrated. 
He  had  also,  with  the  modesty  which  they  all  knew  him  to 
possess,  forgotten  to  mention  that  he  himself  was  the  inventor 
and  founder  of  this  industry,  which  must  compete  in  importance 
and  interest  with  any  other  industry,  either  in  England  or  any 
part  of  the  civilised  world. 


IV.:    i88o 

THE    NEWER   ARTIFICIAL    COLOURING 
MATTERS  DERIVED  FROM  BENZENE 

BY  R.  J.  FRISWELL,  F.C.S.,  F.I.C. 

(Journal  of  the  Society  of  Arts^  1880,  p.  444) 

METHYL  ANILINE  VIOLETS 

IT  is,  no  doubt,  well  known  to  many  here  that  the  earliest 
violets  obtained  by  artificial  means  were  those  produced  by  the 
action  of  pure  aniline,  or  phenylamine,  on  roseine  (magenta), 
in  the  presence  of  an  organic  acid.  A  study  of  this  reaction 
by  Hofmann  led  to  his  discovery  of  the  action  of  the  iodides  of 
the  alcoholic  radicals,  methyl  and  ethyl,  on  roseine  base,  with 
the  production  of  the  well-known  "  Hofmann  Violets."  These 
were  found  to  be  substitution-products  of  rosaniline,  in  which 
one,  two,  or  three  atoms  of  hydrogen  in  the  molecule  are 
replaced  by  the  radicals  methyl  or  ethyl,  according  as  the 
iodide  of  either  has  been  used. 

Now  roseine  itself  is,  as  is  well  known,  produced  by  the 
action  of  arsenic  acid  or  other  oxidising  agents  on  a  mixture 
of  aniline  and  toluidine.  The  chemical  formula  then  adopted 
for  it  led  to  the  conclusion  that  it  was  produced  by  the 
coalescence  of  the  residues  of  two  molecules  of  toluidine  and 
one  of  aniline,  thus  : — 

C6H5NH2  +  2C6H4CH3NH2  -  H6  =  C20H19N3. 

O.  and  E.  Fischer  have  recently  shown  that  this  formula  was 
partly  erroneous,  and  that  the  reaction  could  also  occur  between 
two  molecules  of  aniline  and  one  of  paratoluidine — 

2(C6H5NH2)  +  C6H4CH3NH2  -  H6  -  C19HWN8 ; 


NEWER   ARTIFICIAL   COLOURING   MATTERS     61 

but  this  does  not  affect  the  inference  drawn  from  what  was,  till 
recently,  supposed  to  be  the  constitutional  formula  of  the  body 
in  question,  and  this  inference  was  that  the  methylated 
derivatives  of  roseine  could  be  obtained  by  the  oxidation  of 
the  methylated  derivatives  of  aniline,  just  as  roseine  was  by  the 
oxidation  of  aniline  and  toluidine.  The  inference  was  somewhat 
rash  ;  the  methyl  groups  in  dimethylaniline  replace  the  hydrogens 
in  the  amido  group,  and  on  oxidation  might,  perhaps,  be 
destroyed.  However,  on  oxidation,  dimethylaniline  did,  indeed, 
produce  a  very  brilliant  violet  colour,  which,  having  been 
discovered  by  M.  Lauth,  and  improved  and  patented  by  Messrs 
Poirrier  &  Chappat,  was  introduced  into  commerce  under  the 
name  of  Paris  Violet.  This  achievement  led  to  a  demand  for 
the  production  of  the  methyl  anilines  on  a  large  scale,  and,  in  a 
very  short  time,  this  was  attained.  It  was  well  known  that 
methylaniline  could  be  produced  by  the  action  of  methyl  iodide, 
or  bromide,  upon  aniline,  the  dimethyl  compound  resulting 
from  the  use  of  two  molecules  of  the  alcoholic  compound  ;  thus 

C6H5NH2  +  2(CH8I)  =  C6H5N(CH3)2  +  2HI ; 

but  it  was  evidently  necessary  to  produce  the  required  compound 
in  a  cheaper  way.  This  was  eventually  done  by  heating  aniline 
hydrochloride  and  methylic  alcohol  together,  under  pressure,  in 
strong  cast-iron  vessels,  enamelled  inside,  and  known  as 
"  autoclaves."  Various  proportions  of  the  bodies  have  been 
employed — among  others,  the  following  giving  good  results  : — 
Aniline,  33*6  ;  hydrochloric  acid,  37*9  ;  methylic  alcohol  pure, 
28-5  ;  heat  to  250°  C.  for  eight  hours.  Messrs  Poirrier  have 
also  employed  a  mixture  of  100  parts  aniline  and  250  methyl 
nitrate.  In  the  latter  case,  the  mixture  requires  only  a  temperature 
of  1 00°  C.  ;  but  the  alcoholic  nitrate  is  an  exceedingly  dangerous 
compound  to  deal  with  ;  in  all  probability,  it  was  the  one  that 
led  to  the  lamented  death  of  Mr  E.  T.  Chapman,  and  a  very 
disastrous  and  fatal  explosion  at  Messrs  Poirrier's  works  was 
also  caused  by  it. 

Methylaniline  is  now  largely  made  by  the  action  of  methyl 
chloride  on  aniline.  As  is  well  known,  the  former  body  has, 
of  late  years,  been  obtained  in  immense  quantities  in  France, 
from  a  product  of  the  destructive  distillation  of  residues  obtained 
in  the  manufacture  of  beet  sugar.  This  body  reacts  upon 
aniline  just  as  the  corresponding  iodide  or  bromide  does  ;  it  is 


62  THE   BRITISH   COAL-TAR   INDUSTRY 

cheap,  the  reaction  takes  place  with  ease,  and  a  remarkably 
pure  product  is  produced  :  in  fact,  dimethylaniline  can  now  be 
obtained  by  the  ton,  free  from  unaltered  aniline,  and  containing 
only  3  per  cent,  of  the  monomethylated  compound. 

From  dimethylaniline  the  violet  is  obtained  by  oxidation  ; 
formerly,  various  oxidising  agents  were  used,  among  them  a 
mixture  of  iodine  and  potassium  chlorate  ;  it  is,  however,  now 
well  known  that  very  gentle  oxidisers  will  produce  the  colour 
if  a  metallic  salt  is  present,  the  one  preferred  being  copper.  If 
I  heat,  in  this  tube,  some  copper  filings  with  a  mixture  of 
dimethylaniline  and  chloral  hydrate,  the  whole  will  shortly 
become  a  mass  of  semi-solid  violet.  It  is,  however,  obvious 
that  so  costly  a  method  could  not  be  employed  on  a  manufacturing 
scale,  and,  accordingly,  the  following  process  is  in  very  general 
use  : — 20  parts  pure  crystallised  cupric  nitrate  are  dissolved 
in  20  parts  of  acetic  acid  ;  some  common  salt  is  now  stirred  in 
to  the  mixture,  which  is  carefully  cooled  down  to  the  ordinary 
temperature,  and  50  parts  of  dimethylaniline  are  added  ;  the 
whole  is  then  thoroughly  mixed  with  about  250  to  300  parts 
of  white  sand,  and  the  stiff  mass  thus  produced  is  moulded  into 
large  cakes,  2  feet  long  by  15  inches  wide,  and  4  inches  thick  ; 
these,  arranged  on  copper  plates,  are  placed  in  a  chamber,  and 
heated  to  a  temperature  of  60°  C.  for  forty-eight  hours.  At  the 
end  of  that  time,  they  have  become  perfectly  hard  and  brittle, 
and  of  a  bright  brassy  colour.  They  are  broken  into  a  coarse 
powder  and  thrown  into  water,  sulphide  of  sodium  being  added 
until  the  whole  of  the  copper-salt  has  been  decomposed.  The 
mass  is  now  washed  with  water  and  extracted  with  dilute  hydro- 
chloric acid  at  a  boiling  temperature.  After  partial  cooling  and 
filtration,  to  remove  some  resinous  bye-products,  the  colouring 
matter  is  precipitated  with  common  salt,  and,  after  drying,  it  is 
ready  for  use.  The  sand,  which  simply  serves  to  spread  the 
mixture  over  a  large  surface,  can  be  used  for  a  fresh  operation. 

The  product  thus  obtained  is  very  brilliant  in  colour,  and 
in  shade  is  that  known  as  3  B,  dahlia,  etc.  ;  it  is,  however,  not 
the  bluest  that  can  be  produced.  The  bluest  shades  are  made 
by  dissolving  it  in  alcohol,  converting  it  into  base  by  the  cautious 
addition  of  caustic  soda,  and  then  heating  the  alcoholic  solution 
of  the  base  with  benzyl  chloride — a  body  having  the  formula 
C6H5CH2C1,  and  produced  by  the  action  of  chlorine  on 
toluene.  The  spirit  and  unaltered  benzyl  chloride  are  re- 


NEWER   ARTIFICIAL   COLOURING   MATTERS     63 

covered,  and  the  basic  colour,  on  conversion  into  the  hydro- 
chloride,  is  ready  for  use.  In  a  similar  way,  by  the  action  of 
methyl  chloride,  the  well-known  methyl  green  was  produced  ; 
it  is  now,  however,  replaced  by  the  malachite  green,  discovered 
by  Oscar  Doebner,  and  produced  by  the  action  of  one  molecule  of 
benzoyl  trichloride,  C6H5CC13,  on  two  molecules  of  dimethyl- 
aniline  or  of  benzoylhydride,  or  bitter  almond  oil,  C6H5COH,  on 
the  same,  in  the  presence  of  zinc  chloride  or  of  sulphuric  acid. 

The  latter  colour  much  surpasses  the  former  in  fastness  and 
power  of  standing  rough  treatment  in  the  dyeing  process.  The 
methyl,  and,  still  more,  the  iodine  green,  obtained  during  the 
manufacture  of  blue  shades  of  Hofmann  violet  were  fugitive  and 
easily  altered  by  heat,  so  that  the  latter  could  not  be  boiled 
without  changing  to  a  violet. 

Before  leaving  the  methylaniline  colours,  I  may  briefly  allude 
to  a  question  of  scientific  interest  in  connection  with  them.  It  is 
well  known  that  Hofmann  himself,  at  one  time,  considered  the 
violets  obtained  by  the  methylation  of  rosaniline  and  those  from 
methylaniline  to  be  identical.  On  the  other  hand,  there  was 
much  evidence  against  this  view,  for  the  methylaniline  colour 
was  readily  rendered  bluer  in  shade  by  benzyl  chloride,  which 
was  almost  without  action  on  Hofmann  violet  ;  it  was  also  more 
brilliant,  had  a  much  greater  affinity  for  animal  fabrics,  and  was 
less  permanent  when  exposed  to  light.  For  these  reasons,  the 
Hofmann  colour  is  still  in  demand,  and,  indeed,  has  recovered 
some  of  the  ground  it  at  first  lost  to  the  more  brilliant  colour. 
The  researches  of  Brunner  and  Brandenburg,  following  those  of 
Caro  and  Graebe,  have  shown  that  the  methylaniline  violets  are 
not  identical  with  those  obtained  by  Hofmann's  process. 

DlPHENYLAMINE    BLUE    AND    ALKALI    GREEN 

The  ordinary  aniline  blues  are  obtained  by  the  action  of 
aniline  upon  roseine  base,  in  the  presence  of  an  organic  acid,  at  a 
temperature  which  ultimately  approaches  the  boiling-point  of 
the  aniline  used.  The  ultimate  product  of  this  reaction  is  an 
exceedingly  intense  blue,  the  hydrochloride  of  which  is  known 
as  opal  blue,  and  is,  really,  the  hydrochloride  of  triphenylrosaniline. 
This,  on  dry  distillation,  yields  diphenylamine,  and  the  latter 
body,  on  oxidation,  yields  a  blue  which  is  identical  with  that 
obtained  from  rosaniline,  but  somewhat  greener  in  shade,  and  is 


64  THE   BRITISH   COAL-TAR   INDUSTRY 

therefore  in  demand  for  certain  uses.  The  diphenylamine  is 
prepared  by  heating,  under  pressure,  a  mixture  of  aniline  and  dry 
aniline  hydrochloride,  when  the  following  reaction  occurs  : — 

C6H5NH2  +  C6H6NH2HC1  =  (C6H5)2NH  +  NH4C1. 

Diphenylamine  is  readily  oxidised  if  heated  with  oxalic  acid,  and 
the  resulting  melt,  purified  from  unaltered  oxalic  acid,  diphenyl- 
amine, and  resinous  matters,  is  readily  converted  into  either  of 
the  sulphonic  compounds  discovered  by  Nicholson.  Blues  of  a 
redder  shade  can  be  also  obtained  by  the  oxidation  of  methyl-  or 
ethyldiphenylamine. 

I  have  now  to  call  your  attention  to  a  green  obtained  from 
this  body,  discovered  by  Mr  R.  Meldola,  and  now  under  his 
investigation.  It  is  obtained  by  the  oxidation  of  a  diphenylamine 
derivative.  After  oxidation  the  colour  is  obtained  in  a  state 
corresponding  to  the  well-known  opal  blue,  and,  like  that,  forms 
sulphonic  acids.  It  is  remarkable  as  being  the  first  green  obtained 
having  this  property.  The  sodium  salt  of  the  sulphonic  acid  is 
soluble  in  water,  and,  if  wool  is  immersed  in  this  solution  (which 
is  nearly  colourless),  and  kept  warm,  it  apparently  undergoes  but 
slight  change.  I  have  here  a  piece  of  Berlin  wool  which  has 
been  thus  treated,  and  subsequently  dried.  You  will  observe 
that  it  is,  apparently,  only  rather  dirtier  than  undyed  wool. 
When,  however,  I  immerse  it  in  warm  water,  acidulated  with 
sulphuric  acid,  a  brilliant  green  is  immediately  developed.  The 
colour  is  remarkably  fast  ;  and,  since  it  requires  exactly  the  same 
dyeing  process  as  do  the  Nicholson  blues  for  wool,  one  would 
have  supposed  that  it  would  have  been  much  liked  by  the  dyers  ; 
but  this  is  not,  at  present,  the  case.  It  was  exhibited  at  the  late 
Paris  Exhibition  by  the  firm  of  Brooke,  Simpson,  &  Spiller. 

As  time  is  getting  on,  I  must  now  leave  this  very  interesting 
field — the  colours  produced  by  the  oxidation  of  the  secondary  and 
tertiary  amines — after  a  very  brief  and  incomplete  glance  at  a  few 
of  them,  and  pass  on  to  the  consideration  of  a  totally  distinct 
group  of  colouring  matters,  which  are  now  attracting  much 
attention  in  colour-chemists'  laboratories,  and  which  have  already 
taken  an  important  place  among  artificial  dyes,  though,  as  yet, 
the  range  of  shades  is  somewhat  limited.  These  are  obtained 
from  substances  produced  by  the  action  of  nitrites  on  amido 
compounds,  and  are  known  as  the  azo  yellows,  oranges,  and 
scarlets. 


THE  NEWER  ARTIFICIAL  COLOURING  MATTERS  65 

The  effect  of  nitrites  on  organic  compounds  is  very  various, 
according  to  the  subsequent  treatment  they  undergo  ;  thus,  if 
nitrous  gas  is  passed  through  a  solution  of  diphenylamine  in 
acetic  acid,  a  mixture  of  nitroso-nitro-diphenylamines  results,  and 
this,  on  heating  with  an  alkali,  decomposes  so  far  as  the  nitroso 
groups  are  concerned,  and  a  mixture  of  mono-  and  dinitro- 
diphenylamine  results,  which  was  introduced  as  a  yellow  dye  by 
Mr  R.  Meldola.  A  somewhat  similar  reaction  occurs  if  the 
sulphonic  acid  of  alpha-naphthol  is  similarly  treated,  and  dinitro- 
naphthol  may  be  obtained  ;  while,  if  a  nitrite  is  added  to  an 
aniline  salt,  and  the  resulting  compound  boiled,  or  if  rosaniline 
salts  are  similarly  treated,  the  whole  of  the  nitrogen  is  eliminated 
with  effervescence,  and  phenol  in  the  one  case,  rosolic  acid  in  the 
other — both  of  them  non-nitrogenous  substances — result.  Before 
this  boiling  takes  place,  there  are,  however,  in  the  two  latter  cases, 
very  different  bodies  in  solution  ;  these  bodies,  which  behave  in 
the  manner  just  mentioned  on  boiling,  are  known  to  chemists  as 
"  azo  compounds." 

In  the  earlier  days  of  organic  chemistry,  the  prefix  "  azo  " 
was  applied  by  Mitscherlich,  Laurent,  Zinin,  and  others  to 
many  bodies  containing  nitrogen,  such  as  azo  -  benzene, 
C6H5N=NC6H5,  produced  by  the  imperfect  reduction  of  nitro- 
benzene, and  also  to  others,  like  the  compounds  obtained  by 
Laurent  by  the  action  of  ammonia  on  bitter-almond  oil  and 
other  bodies.  In  1864,  however,  P.  Griess  published  a 
magnificent  memoir,  in  which  he  described  a  number  of  bodies 
obtained  by  the  action  of  nitrous  acid  on  aniline,  and  various 
substitution-products  obtained  therefrom.  In  this  paper,  he 
proposed  that  the  prefix  "  azo "  should  be  held  to  mean  that 
the  compound  to  which  it  was  applied  contained  one  atom  of 
nitrogen  occupying  the  place  of  one  atom  of  hydrogen.  This 
definition  is  now  generally  accepted,  and  thus  the  term  "  azo  " 
has  obtained  a  definite  signification. 

The  azo  compounds  are,  as  a  rule,  very  easily  prepared  ;  in 
most  cases,  it  is  only  necessary  to  add  a  solution  of  metallic 
nitrite  to  an  acid  solution  of  a  given  amide,  in  order  to  obtain 
the  diazo  compound  of  the  radicle  contained  in  the  amide  ; 
thus,  if  I  take  a  solution  of  aniline  hydrochloride,  and  add  to  it 
an  equivalent  quantity  of  sodium  nitrite  solution,  the  reaction 
at  once  takes  place,  and  the  diazobenzene  is  produced  ;  it  can 
be  readily  separated  from  its  solution,  and  obtained  in  the  solid 

5 


66  THE   BRITISH   COAL-TAR   INDUSTRY 

state,  one  method  being  to  add  a  solution  of  potassium  dichromate, 
when  the  chlorochromate  of  diazobenzene  is  produced.  This 
salt,  when  dry,  is  terribly  explosive,  and  at  one  time  was 
suggested  for  use  in  warlike  operations  ;  however,  it  very 
rapidly  decomposes  when  kept,  losing  nitrogen,  and  becoming 
no  longer  efficient. 

This  explosiveness  is  readily  understood  when  we  consider 
the  constitution  of  the  body  which  contains  the  group — N=N — . 
It  is  manifestly  in  a  state  of  unstable  equilibrium,  and  a  very 
slight  disturbance  is  sufficient  to  bring  about  its  decomposition  ; 
and,  for  the  same  reason,  you  will  at  once  see  that  its  chemical 
activity,  as  measured  by  its  tendency  to  combine  with  other 
bodies,  will  be  great ;  so  that,  if  I  add  to  it  another  molecule 
of  aniline  salt,  or,  what  amounts  to  the  same  thing,  if  I  add  to 
two  molecules  of  aniline  only  one  of  sodium  nitrite,  the 
diazobenzene  formed  at  once  attacks  the  free  aniline  salt,  and 
what  is  known  as  diazoamidobenzene  is  formed,  which,  in  the 
presence  of  an  aniline  salt,  becomes  amidoazobenzene — 
C6H5N=NC6H4NH2.  The  oxalate  of  this  body  was  once  in 
pretty  general  use  as  a  yellow  dye,  but,  as  it  happened  to  be 
volatile  at  a  very  low  temperature,  it  soon  evaporated  from  the 
dyed  article,  and  was,  therefore,  discarded. 

A  compound  having  a  very  similar  constitution  and  mode 
of  preparation  has,  however,  long  been  in  use,  under  the  name 
of  "  Bismarck  brown,"  and  is  one  of  the  most  permanent  of  the 
aniline  colours.  It  is  obtained  as  follows  : — 

Metadinitrobenzene  is  prepared  by  boiling  ordinary  nitro- 
benzene with  nitric  acid.  The  compound  thus  produced  is 
added  cautiously,  with  constant  agitation,  to  coarse  iron  borings, 
kept  boiling  in  a  large  quantity  of  water  acidulated  with  hydro- 
chloric acid.  A  violent  reaction  soon  commences  (I  could  readily 
show  you  the  experiment,  but  for  the  steam  and  unpleasant 
odour  produced)  ;  the  four  oxygen  atoms  contained  in  the 
dinitrobenzene  are  replaced  by  hydrogen,  thus  : — 

4C6H4(N02)2  -h  Fe15  +  4OH2  =  4C6H4(NH2)2  +  S(Fe3O4). 

We  have  thus  produced  diamidobenzene,  and  this,  when 
purified  from  a  little  dissolved  iron,  is  attacked  with  sodium 
nitrite  solution  ;  the  reaction  here  is  analogous  to  the  one  last 
described,  the  final  product  of  the  reaction  being  a  triamido- 
azobenzene,  the  hydrochloride  of  which  constitutes  the  well- 


THE  NEWER  ARTIFICIAL  COLOURING  MATTERS  67 

known  colouring  matter.  We  have  thus  two  terms  of  a  possible 
series — first,  the  amido-azobenzene  (yellow,  volatile,  and  fugitive), 
and  triamido-azobenzene  (brown,  and  perfectly  fast).  Dr  Witt 
set  himself  the  task  of  filling  up  the  intermediate  link,  expecting 
an  orange  colour,  and  a  moderate  stability  for  the  diamido- 
azobenzene  he  sought.  In  this  he  was  not  disappointed.  A 
study  of  the  two  compounds,  from  a  purely  scientific  point  of 
view,  led  him  to  a  perfectly  accurate  prediction  ;  and  the 
discovery  of  "  chrysoidine,"  as  the  new  colour  was  called,  and 
its  production — by  the  addition  of  diazobenzone  chloride  to  a 
solution  of  diamidobenzene — was  one  of  the  first  of  a  series  of 
researches  which  have,  in  various  hands,  enriched  our  science  and 
our  dyers  with  a  number  of  magnificent  colours. 

The  further  development  of  these  colours  commenced  with 
the  introduction  of  a  sulphonic  group  into  one  of  the  amido 
compounds,  the  conversion  of  the  sulphonic  acid  thus  produced 
into  a  diazo  body,  and  then  using  it  as  before  ;  for  instance,  if 
sulphanilic  acid — produced  by  the  action  of  strong  sulphuric  acid 
on  aniline — is  converted  into  diazosulphanilic  acid,  and  this  added 
to  a  solution  of  diamidobenzene-hydrochloride,  the  scarlet  body 
produced  is  the  sulphonic  acid  of  chrysoidine.  Again,  the  same 
body  will  act  on  resorcine  to  produce  a  colour  only  differing  from 
the  last  in  that  it  contains  hydroxyl  instead  of  amido  groups  ; 
this  body  has  been  used  as  a  dye,  under  the  name  of  tropaeoline 
o.  Witt  also  produced,  by  substituting  diphenylamine  for  the 
resorcine,  or  diamidobenzene,  another  beautiful  orange,  known 
in  commerce  as  tropaeoline  oo.  Other  compounds  were  sub- 
sequently prepared,  and  have  obtained  greater  prominence  ;  these 
were  those  in  which  a  naphthol  was  substituted  for  the  phenolic 
or  amido  portion  of  the  molecule,  beautiful  oranges  being  pro- 
duced by  the  action  of  diazobenzene  sulphonic  acid  on  both  a- 
and  /8-naphthol  ;  but  these  colours  were  much  improved  by  the 
introduction  of  sulphonic  groups  into  both  portions  of  the 
molecule,  a-  or  /3-naphthol-sulphonic  acid  being,  in  fact,  substituted 
for  the  naphthol  only  ;  still,  so  far,  the  improvement  was  in  the 
direction  of  stability  mainly,  the  shades  still  being  yellow  or 
orange  ;  the  red  was  yet  to  come. 

Chemists  will  not  be  surprised  to  hear  that  the  higher  homo- 
logues  of  benzene  are  found,  when  converted  into  amido  com- 
pounds, to  give  an  increased  redness  of  shade  ;  thus,  with  a  given 
phenol  or  amine,  diazosulphotoluidinic  acid,  which  differs  from 


68  THE   BRITISH   COAL-TAR   INDUSTRY 

diazosulphanilic  acid  by  having  an  atom  of  hydrogen  in  the 
benzene  ring  replaced  by  methyl,  gives  redder  shades  than  does 
the  latter,  while  the  substitution  of  another  hydrogen  in  the  same 
way,  as  is  the  case  with  the  diazo  compound  derived  from 
sulphoxylidinic  acid,  produces  a  scarlet.  Messrs  Meister, 
Lucius  &  Brtining  were  among  the  first  to  produce  a  scarlet 
by  this  method,  but  they  also  introduced  both  the  sulpho 
groups  into  one  side  of  the  molecule — that  of  the  naphthol.  In 
their  patent  they  describe  the  preparation  of  two  isomeric  /3- 
naphthol-disulphonic  acids,  the  sodium  salts  of  which  are 
differently  soluble  in  alcohol,  the  most  insoluble  one  giving  a 
redder  colour  than  the  other.  On  one  or  other  of  these  they  act 
with  diazoxylene  chloride,  produced  by  the  action  of  a  nitrite  on 
xylidine  chloride.  The  most  insoluble  salt  above  mentioned  gives 
a  scarlet  closely  approaching  cochineal  scarlet,  and  perfectly  fast. 

Mr  R.  Meldola  has  also  taken  out  a  patent  for  a  scarlet, 
in  which  no  less  than  three  sulpho  groups  are  engaged.  He 
prepares  diazosulphoxylidinic  acid,  and  with  this  acts  on  /3- 
naphthol-disulphonic  acid  ;  on  the  addition  of  ammonia,  the 
colour  is  immediately  thrown  down,  as  you  perceive.  This  is, 
after  a  slight  purification,  ready  for  use.  By  certain  modifications, 
a  scarlet,  closely  approaching  the  scarlet  obtained  by  dyeing 
cochineal  in  the  presence  of  oxychloride  of  tin,  is  produced. 

So  far,  we  have  only  oranges  and  scarlets  by  these  reactions. 
Whether  other  colours  can  be  similarly  produced  remains  to  be 
seen  ;  but  1  may  mention  that  Mr  Meldola  has  recently  com- 
municated a  paper  to  the  Berlin  Chemical  Society,  in  which  he 
describes  a  violet  colour — unfortunately  not  a  dye — obtained 
in  a  somewhat  similar  way.  If  we  act  on  dimethylaniline — the 
body  from  which  the  violets  described  in  the  first  part  of  my 
lecture  are  derived — with  a  nitrate,  not  an  azo  but  a  nitroso- 
dimethylaniline  is  produced,  thus  : — C6H4NON(CH3)2.  This 
body  is  as  ready  to  combine  with  others  as  an  azo  body  is,  and 
does  so  in  a  very  similar  way,  the  oxygen  atom  being  elimin- 
ated in  the  process,  so  that  if  we  act  with  it  on  /3-naphthol  the 
following  combination  takes  place 1  : — 

C6H4.N.N(CH3)2 
/3C10H5OH, 

1  This  formula  is  given  under  reserve,  as  a  complete  investigation  of  the 
compound  has  not  yet  been  published. 


THE  NEWER  ARTIFICIAL  COLOURING  MATTERS  69 

the  oxygen  of  the  nitroso  group  going  off  with  two  hydrogens 
from  the  /3-naphthol,  the  place  of  which  is  taken  by  a  group, 
which  is  equivalent  to  azo-dimethylaniline.  The  colour  crys- 
tallises magnificently,  but  its  dyeing  powers  are  very  feeble. 

DISCUSSION 

Mr  SPILLER  said  it  would  be  manifest  that  the  benzene  dye 
industry  had  of  late  years  made  gigantic  strides.  When  he 
first  became  connected  with  the  industry  it  was  the  rule  to 
select  out  the  benzole  of  the  coal-tar  and  throw  away  a  large 
residual  product  known  as  dead-oil.  But  the  requirements  of 
the  latest  forms  of  colouring  matter  which  had  been  mentioned, 
particularly  the  orange  and  scarlet,  demanded  that  the  dead-oil 
should  be  worked  up  with  a  view  to  extract  from  it  the  toluene 
and  xylene.  Naphthalene  had  for  a  great  number  of  years  been  a 
perfect  bugbear  in  scientific  industry.  It  was  produced  in  immense 
quantities  in  the  manufacture  of  gas,  and,  whilst  by  the  labours 
of  Perkin  and  Graebe  anthracene  had  been  employed  in  the 
manufacture  of  alizarin,  the  naphthalene  had  been  thrown  away. 
It  was,  however,  now  required  for  the  manufacture  of  the 
scarlet  described  by  Mr  Friswell. 

Dr  H.  E.  ARMSTRONG  said  the  paper  ought  to  convey  a 
sound  lesson  to  the  objectors  to  abstract  science,  because  practi- 
cally speaking  the  whole  of  these  colours  were  the  result  of 
investigations  originally  undertaken  without  any  practical  aim. 
There  was  a  large  amount  of  material  still  remaining  in  coal-tar 
not  utilised,  and  there  was  no  doubt  a  great  future  in  that 
direction. 

It  was  not  more  than  ten  or  twelve  years  ago  that  it  was 
found  that  alizarin  could  be  produced  artificially,  and  now 
practically  all  the  Turkey-red  used  was  produced  artificially. 
A  few  years  ago  the  diazo  compounds  were  substances  which 
even  chemists  were  almost  afraid  to  handle.  They  were  discovered 
by  Dr  P.  Griess,  and  were  extremely  unstable  and  difficult  to 
manipulate,  and  it  would  have  appeared  almost  laughable  that 
such  compounds  would  be  used  for  producing  colouring  matters 
on  a  large  scale.  Dr  O.  Witt's  theoretical  views  with  regard 
to  the  constitution  of  colouring  matters  had  been  very  productive, 
and  frequently  enabled  chemists  to  say,  not  only  that  a  certain 
body  would  be  a  colouring  body,  but  would  have  a  certain  shade. 


yo  THE   BRITISH   COAL-TAR   INDUSTRY 

Mr  R.  MELDOLA  said  there  was  no  doubt  that  a  great  many 
of  the  products  that  now  ran  down  our  drains  would  one  day 
become  quite  as  valuable  as  many  of  those  which  were  at  present 
employed  in  factories.  New  diazo  compounds  of  more  and  more 
complex  constitutions  were  being  discovered  continually,  and  their 
number  might  increase  indefinitely. 

The  Chairman  (Prof.  CHARLES  GRAHAM)  said  that  when  it  was 
remembered  that  Faraday  discovered  benzene  before  any  of  them 
were  born,  and  that  Unverdorben  discovered  aniline  long  ago, 
it  was  evident  that  there  must  have  been  much  pure  scientific 
research  carried  on  before  manufacturers  were  able  to  make  use 
of  it  and  convert  the  products  of  coal-tar  distillation  into  the 
valuable  dyeing  materials  we  now  possess. 


V.:    i88i 


INDIGO  AND   ITS  ARTIFICIAL   PRODUCTION 

BY  PROFESSOR  H.  E.  ROSCOE,  LL.D.,  F.R.S. 
(Discourse  delivered  at  the  Royal  Institution,  2yth  May  1881) 

THE  first  portion  of  this  address  deals  with  the  various  syntheses 
of  indigotin  up  to  the  commercial  introduction  of  ortho-nitro-phenyl 
propiolic  acid  in  1881,  and  with  the  mode  of  application  of  that  body. 

Professor  Roscoe  proceeds  as  follows  : — 

The  potential  importance,  from  a  purely  commercial  point  of 
view,  of  the  manufacture  of  synthetic  indigo  may  be  judged  of 
by  reference  to  the  following  statistics,  showing  that  the  annual 
value  of  the  world's  growth  of  indigo  is  no  less  than  four  millions 
sterling. 

ESTIMATED  YEARLY  AVERAGE  OF  THE  PRODUCTION  OF  INDIGO  IN  THE 
WORLD,  TAKEN  FROM  THE  TOTAL  CROP  FOR  A  PERIOD  OF  TEN  YEARS 


Pounds 
weight. 

Pounds 
sterling. 

Bengal,  Tirhoot,  Benares,  and  N.W.  India 
Madras  and  Kurpah         
Manilla,  Java,  Bombay,  etc.     .... 
Central  America      ...... 
China  and  elsewhere,  consumed  in  the  country 

8,000,000 
2,200,000 

2,250,000 

2,000,000 
400,000 
500,000 
600,000 
say  500,000 

4,000,000 

How  far  the  artificial  will  drive  out  the  natural  colouring 
matter  from  the  market  cannot,  as  has  been  said,  be  foreseen. 
It  is  interesting,  as  the  only  instance  of  the  kind  on  record,  to 


72  THE   BRITISH   COAL-TAR   INDUSTRY 

cast  a  glance  at  the  history  of  the  production  of  the  first  of  the 
artificial  vegetable  colouring  matters,  alizarin.  In  this  case  the 
increase  in  the  quantity  produced  since  its  discovery  in  1869 
has  been  enormous,  such  indeed  that  the  artificial  colour  has 
now  entirely  superseded  the  natural  one,  to  the  almost  complete 
annihilation  of  the  growth  of  madder-root.  It  appears  that 
whilst  for  the  ten  years  immediately  preceding  1869  the  aver- 
age value  of  the  annual  imports  of  madder-root  was  over  one 
million  sterling,  the  imports  of  the  same  material  during  last 
year  (1880)  amounted  only  to  £24,000;  the  whole  difference 
being  made  up  by  the  introduction  of  artificial  alizarin.  In 
1868,  no  less  a  quantity  than  60,000  tons  of  madder-root  were 
sent  into  the  market,  this  containing  600,000  kilos  of  pure 
natural  alizarin.  But  ten  years  later  a  quantity  of  artificial 
alizarin  more  than  equal  to  the  above  amount  was  sent  out 
from  the  various  chemical  factories.  So  that  in  ten  years  the 
artificial  production  had  overtaken  the  natural  growth,  and  the 
300,000  or  400,000  acres  of  land  which  had  hitherto  been  used 
for  the  growth  of  madder  can  henceforward  be  better  employed 
in  growing  corn  or  other  articles  of  food.  According  to  returns, 
for  which  the  speaker  had  to  thank  Mr  Perkin,  the  estimated 
growth  of  madder  in  the  world  previous  to  1869  was  90,000 
tons,  of  the  average  value  of  £45  per  ton,  representing  a  total 
of  £4,050,000. 

Last  year  (1880)  the  estimated  production  of  the  artificial 
colouring  matter  was  14,000  tons,  but  this  contains  only  10 
per  cent,  of  pure  alizarin.  Reckoning  i  ton  of  the  artificial 
colouring  matter  as  equal  to  9  tons  of  madder,  the  whole 
artificial  product  is  equivalent  to  126,000  tons  of  madder.  The 
present  value  of  these  14,000  tons  of  alizarin  paste,  at  £122 
per  ton,  is  £1,568,000.  That  of  126,000  tons  of  madder  at 
£45  is  £5,670,000,  or  a  saving  is  effected  by  the  use  of 
alizarin  of  considerably  over  four  millions  sterling.  In  other 
words,  we  get  our  alizarin  dyeing  done  now  for  less  than 
one-third  of  the  price  which  we  had  to  pay  to  have  it  done 
with  madder. 

Our  knowledge  concerning  the  chemistry  of  alizarin  has  also 
proportionately  increased  since  the  above  date.  For  whilst  at 
that  time  only  one  distinct  body  having  the  above  composition 
was  known,  we  are  now  acquainted  with  no  less  than  nine  out  of 
the  ten  di-oxyanthraquinones  the  existence  of  which  is  theoreti- 


INDIGO   AND    ITS   ARTIFICIAL   PRODUCTION    73 

cally  possible,  according  as  the  positions  of  the  two  molecules  of 
hydroxyl  are  changed. 


-co- 


— co- 


Of  the  nine  known  di-oxyanthraquinones,  only  one,  viz. 
alizarin,  or  that  in  which  the  hydroxyls  are  contained  in  the 
position  i,  2,  is  actually  used  as  a  colouring  agent.  Then  again, 
three  tri-oxyanthraquinones,  C14H5O2(OH)3,  are  known.  One 
of  these  is  contained  in  madder-root,  and  has  long  been  known 
as  purpurin.  The  other  tri-oxyanthraquinones  can  be  artificially 
prepared.  One  termed  anthrapurpurin  is  an  important  colour- 
ing matter,  especially  valuable  to  Turkey-red  dyers,  as  giving  a 
full  or  fiery  red.  The  other,  called  flavopurpurin,  gives  an 
orange  dye  with  alumina  mordants.  All  these  various  colouring 
matters  can  now  be  artificially  produced,  and  by  mixing  these  in 
varying  proportions  a  far  greater  variety  of  tints  can  be  obtained 
than  was  possible  with  madder  alone,  and  thus  the  power  of 
diversifying  the  colour  at  will  is  placed  in  the  hands  of  the  dyer 
and  calico-printer. 

It  is  quite  possible  that  in  an  analogous  way  a  variety  of 
shades  of  blue  may  be  ultimately  obtained  from  substituted 
indigos,  and  thus  our  catalogue  of  coal-tar  colours  may  be  still 
further  increased. 

To  Englishmen  it  is  a  somewhat  mortifying  reflection,  that 
whilst  the  raw  materials  from  which  all  these  coal-tar  colours 
are  made  are  produced  in  our  country,  the  finished  and  valuable 
colours  are  nearly  all  manufactured  in  Germany.  The  crude 
and  inexpensive  materials  are,  therefore,  exported  by  us  abroad, 
to  be  converted  into  colours  having  many  hundred  times  the 
value,  and  these  expensive  colours  have  again  to  be  bought  by 
English  dyers  and  calico-printers  for  use  in  our  staple  industries. 
The  total  annual  value  of  manufactured  coal-tar  colours  amounts 
to  about  three  and  a  half  millions  ;  and  as  England  herself, 
though  furnishing  all  the  raw  material,  makes  only  a  small 
fraction  of  this  quantity,  but  uses  a  large  fraction,  it  is  clear 
that  she  loses  the  profit  on  the  manufacture.  The  causes  of 


74  THE    BRITISH    COAL-TAR    INDUSTRY 

this  fact,  which  we  must  acknowledge,  viz.  that  Germany  has 
driven  England  out  of  the  field  in  this  important  branch  of 
chemical  manufacture,  are  probably  various.  In  the  first  place, 
there  is  no  doubt  that  much  of  the  German  success  is  due  to 
the  long-continued  attention  which  their  numerous  universities 
have  paid  to  the  cultivation  of  organic  chemistry  as  a  pure 
science.  For  this  is  carried  out  with  a  degree  of  completeness, 
and  to  an  extent,  to  which  we  in  England  are  as  yet  strangers. 
Secondly,  much  again  is  to  be  attributed  to  the  far  more  general 
recognition  amongst  German  than  amongst  English  men  of 
business  of  the  value,  from  a  merely  mercantile  point  of  view,  of 
high  scientific  training.  In  proof  of  this  it  may  be  mentioned,  that 
each  of  two  of  the  largest  German  colour-works  employs  no  less  a 
number  than  from  twenty-five  to  thirty  highly  educated  scientific 
chemists,  at  salaries  varying  from  £250  to  ^500  or  j£6oo  per 
annum.  A  third  cause  which  doubtless  exerts  a  great  influence 
in  this  matter  is  the  English  law  of  patents.  This,  in  the  special 
case  of  colouring  matters  at  least,  offers  no  protection  to  English 
patentees  against  foreign  infringement,  for  when  these  colours 
are  once  on  the  goods  they  cannot  be  identified.  Foreign 
infringers  can  thus  lower  the  price  so  that  only  the  patentee, 
if  skilful,  can  compete  against  them,  and  no  English  licensees 
of  the  patent  can  exist.  This  may  to  some  extent  account  for 
the  reluctance  which  English  capitalists  feel  in  embarking  in 
the  manufacture  of  artificial  colouring  matters.  That  England 
possesses  both  in  the  scientific  and  in  the  practical  direction 
ability  equal  to  the  occasion,  none  can  doubt.  But  be  that  as 
it  may,  the  whole  honour  of  the  discovery  of  artificial  indigo 
belongs  to  Germany  and  to  the  distinguished  chemist  Professor 
Adolf  Baeyer,  whilst  towards  the  solution  of  the  difficult  problem 
of  its  economic  manufacture  the  first  successful  steps  have  been 
taken  by  Dr  Caro  and  the  Baden  Aniline  and  Soda  Works  of 
Mannheim. 


VI. :    1885 

THE  COLOURING  MATTERS  PRODUCED 
FROM   COAL-TAR 

BY  W.  H.  PERKIN,  F.R.S. 

(Presidential  Address,  Society  of  Chemical  Industry,  1885  : 
Jour.  Soc.  Chem.  Ind.,  1885,  p.  426) 

TAKING  a  precedent  from  some  of  those  who  have  occupied 
this  chair  before  me,  I  have  selected  for  my  few  remarks  to-day 
the  subject  in  relation  to  Technical  Chemistry,  with  which  I  have 
been  personally  connected — namely,  the  colouring  matters  pro- 
duced from  coal-tar  products,  with  some  of  the  lessons  its 
development  appears  to  me  to  teach  us  in  connection  with 
industrial  chemistry.  Sir  Frederick  Abel,  in  his  address  in  1883, 
when  speaking  of  the  history  of  gunpowder,  said  that  "  It  is  one 
of  the  most  remarkable  features  connected  with  the  history  of 
gunpowder,  that  until  the  last  quarter  of  a  century  no  radical 
changes  should  have  been  introduced  into  the  manufacture  and 
modes  of  applying  this,  the  first  known  practically  useful 
explosive  agent."  It  appears  to  me  that  this  is  more  or  less 
true  of  all  the  older  industries,  which  resulted  simply  from 
experiment  and  observation  without  any  other  basis  to  work 
from.  They  have  had  long  histories  in  which  little  progress  has 
been  made,  but  of  late  years,  owing  to  our  advanced  and  rapidly 
increasing  scientific  knowledge,  they  are  undergoing  great,  and 
in  many  cases  radical,  changes. 

The  coal-tar  colour  industry  stands  in  a  very  different  position 
to  our  older  ones.  It  has  a  sharply  defined  origin,  and  a  very 
short  history  dating  back  only  to  1856,  and  it  is  not  yet  twenty-nine 
years  since  the  date  of  the  first  patent.  It  is  an  industry  which  has 
been  founded  on  scientific  discovery,  and  has  developed  side  by 
side  with  it,  being  in  fact  a  most  important  handmaid  to  research, 

75 


76  THE   BRITISH   COAL-TAR   INDUSTRY 

which  in  its  turn  has  repaid  it  by  new  discoveries.  At  the  date 
of  its  introduction  very  little  was  known  of  the  chemistry  of 
colouring  matters  ;  they  were  always  found  difficult  bodies  to 
investigate,  and  when  produced  in  reactions  were  generally 
regarded  as  secondary  products,  and  every  endeavour  was  made 
to  get  rid  of  them  so  that  the  other  products  associated  with  them 
might  be  examined  ;  but  now,  owing  to  the  very  extended  study 
which  has  been  made  of  these  bodies,  on  account  of  this  industry, 
and  the  relationships  which  have  been  found  to  exist  between  the 
colour  of  the  compounds  and  the  chemical  constitution,  it  is 
possible  with  more  or  less  certainty  to  predict  the  colour  a  com- 
pound will  have  before  it  is  produced,  and  the  means  which  can 
be  used  to  modify  it. 

It  will  be  possible  for  me  to  give  you  only  a  very  brief  sketch 
of  the  history  of  this  industry  in  the  time  at  my  disposal  ;  any- 
thing like  a  complete  account  would  fill  volumes.  On  account 
of  this  I  shall  not  be  able  to  refer  except  casually  to  the  coal- 
tar  industry  itself,  the  development  of  which  is  mainly  due 
to  the  one  under  consideration.  Nor  can  I  give  a  consecutive 
account  of  the  coal-tar  colours  themselves,  because  the  discovery 
of  new  series  of  colouring  matters,  and  the  progress  of  old  ones, 
necessarily  produce  overlapping  as  it  were,  and  renders  such  a 
course  difficult  and  confusing.  I  therefore  propose  to  take  them 
according  to  the  groups  we  now  know  them  to  belong  to.  I  will 
therefore  commence  with  that  which  contains  the  first  colouring 
matter  connected  with  this  industry  —  i.e.  the  mauveine  and 
safranine  group  of  compounds. 

As  I  already  mentioned,  the  coal-tar  colour  industry  dates 
from  1856,  the  discovery  of  the  aniline  purple  or  mauve  dye 
being  made  during  the  Easter  vacation  of  that  year,  and  the 
patent  for  its  production  taken  out  on  the  26th  of  the  following 
August.  I  have  already  described  elsewhere  *  how  the  discovery 
of  this  colouring  matter  was  made  during  the  prosecution  of 
scientific  research  which  had  for  its  object  the  artificial  production 
of  quinine,  a  subject  which  of  late  has  very  much  occupied  the 
attention  of  chemists,  though  it  has  not  as  yet  been  accomplished. 

When  commencing  this  industry,  which  was  looked  upon  by 
many  with  considerable  doubt  as  to  its  practicability,  the  diffi- 
culties encountered  were  very  numerous  on  account  of  its  unique 
character,  but  few  of  the  processes  having  their  representatives 

1  See  p.  5,  ante. 


COLOURING   MATTERS   FROM    COAL-TAR      77 

in  other  industries  ;  the  products  were  also  very  valuable,  so  that 
great  care  had  to  be  employed  with  them.  Moreover,  the  success 
of  the  product  tinctorially  had  not  been  proved  on  the  large  scale, 
so  that  it  was  necessary  to  proceed  tentatively  and  not  launch  out 
too  rapidly. 

Aniline,  as  is  well  known,  was  at  this  period  a  rare  body, 
originally  obtained  from  indigo  by  Unverdorben  in  1826  ;  for 
its  production  from  benzene  we  are  first  indebted  to  the  discovery 
of  nitrobenzene  in  1834  by  Mitscherlich,  and  then  to  Zinin,  who 
found  that  this  substance  when  submitted  to  certain  reducing 
agents  produced  a  base  which  was  eventually  identified  as  aniline. 
It  was  not  long  before  the  date  of  this  industry  that  a  method 
of  producing  this  base  from  nitrobenzene,  with  greater  ease  than 
by  the  process  of  Zinin,  was  discovered  ;  and  it  is  to  Bechamp 
we  are  indebted  for  this,  who  found  that  the  reduction  might  be 
easily  accomplished  by  means  of  iron  filings  and  acetic  acid.  Had 
this  discovery  not  been  made,  aniline  could  not  have  been  pro- 
duced sufficiently  cheap  to  be  used  for  the  production  of  colour- 
ing matters.  And  it  is  interesting  to  note  that  this  process  of 
Bechamp,  slightly  modified,  is  the  one  used  to-day  for  the  pro- 
duction not  only  of  this  base,  but  its  homologues  and  analogous 
compounds. 

It  was  not  long  before  the  difficulties  of  producing  nitro- 
benzene were  to  a  great  extent  overcome.  Messrs  Simpson, 
Maule  &  Nicholson  also  began  to  experiment  on  the  production 
of  nitrobenzene,  and  after  a  time  were  able  to  produce  it  at  a 
sufficiently  low  cost  to  be  able  to  supply  us  with  part  of  our 
requirements.  I  mention  this  in  passing  because  it  was  the 
starting-point  of  the  history  of  the  connection  of  this  firm  with 
artificial  production  of  colouring  matter,  which  they  carried  on 
so  successfully  afterwards. 

After  the  mauve  was  discovered  it  was  necessary  to  teach 
dyers  how  to  use  it.  Being  an  organic  base,  it  is  opposite  in 
properties  to  the  vegetable  colouring  matter,  and  therefore  the 
ordinary  methods  of  application  were  not  generally  useful,  and 
much  time  had  to  be  spent  in  dye-houses  and  print-works  in  the 
early  days  of  this  product  in  reference  to  this  subject,  and  at  that 
time  the  question  of  fastness  to  light,  soap,  and  bleaching  liquor 
was  much  insisted  on.  Fortunately  for  the  future  of  the  coal-tar 
colour  industry,  although  the  mauve  would  not  resist  bleaching 
liquor  well,  it  proved  to  be  a  very  fast  colour — the  fastest  purple 


78  THE   BRITISH    COAL-TAR    INDUSTRY 

yet  produced,  I  believe — and  thus  its  introduction  became  rapid. 
After  this  the  love  of  brilliancy  of  colour  which  it  had  induced 
caused  less  attention  to  be  given  to  the  subject  of  fastness.  I 
quite  think  that  had  this,  the  first  coal-tar  colouring  matter, 
yielded  colours  as  fugitive  as  some  which  have  since  been  used, 
this  industry  would  probably  have  been,  to  say  the  least,  much 
delayed  in  its  progress  ;  so  that  it  will  be  seen  the  mauve  had  to 
bear  all  the  burdens  of  the  difficulties  incident  on  the  inauguration 
of  this  industry,  the  future  products  being  free  from  these 
impediments.  The  importance  of  this  colouring  matter  after  its 
success  was  established  was  quickly  recognised  in  France,  and  its 
manufacture  commenced  there.  This  soon  resulted  in  its  importa- 
tion into  this  country  irrespective  of  patent  rights.  As,  however, 
the  foreign  manufacturer  employed  responsible  agents  in  this 
country,  the  law  was  without  difficulty  put  into  operation  success- 
fully— unfortunately,  however,  only  to  teach  Continental  manu- 
facturers the  lesson  not  to  employ  responsible  agents  in  this 
country  any  longer,  but,  by  means  of  correspondence  or  travellers 
to  deal  directly  with  the  consumers,  and  this  modus  operandi 
(practically,  though  perhaps  not  theoretically)  enabled  them  to 
ignore  the  existence  of  patents,  and  import  their  products  freely 
into  this  country.  On  this  point  I  shall  have  to  speak  again 
further  on.  The  mauve  was  first  employed  in  silk  dyeing  in 
London,  Messrs  Thomas  Keith  &  Sons,  of  Bethnal  Green,  being 
the  first  to  use  it.  The  second  application  was  calico  printing, 
Messrs  James  Black  &  Co.,  of  Glasgow,  being  the  first  to 
employ  it  largely  for  this  purpose.  It  afterwards  was  extended 
to  other  trades. 

With  reference  to  the  chemical  history  of  this  dye,  although 
it  had  been  submitted  to  analysis  very  soon  after  its  discovery, 
its  formula,  or  rather  the  formula  of  its  principal  constituent 
"  mauveine,"  was  not  established  until  some  time  after  it  had 
become  a  commercial  product,  and  was  prepared  in  a  crystalline 
condition.  It  was  then  shown  to  have  the  composition  C27H24N4 
(Proc.  R.S.y  xiii.  170). 

It  was  found  to  be  a  very  powerful  base,  decomposing 
ammonia  salts  with  evolution  of  ammonia,  and  combining  with 
carbonic  acid  to  form  a  carbonate.  Its  ordinary  salts  are  pro- 
duced by  its  combination  with  one  molecule  of  a  monobasic 
acid,  its  hydrochloride  having  the  formula  C27H24N4HC1. 

In  concentrated  sulphuric  acid  mauveine  dissolves  with  a  dirty 


COLOURING    MATTERS   FROM    COAL-TAR      79 

green  colour,  changing  to  blue  on  slight  dilution,  and  back  to 
purple  when  thoroughly  diluted  ;  this  is  a  distinctive  reaction  of 
this  class  of  colouring  matters.  Further  researches  have  shown 
(Jour.  Chem.  Soc.,  xxxv.  717—732)  that  in  the  ordinary  commercial 
product,  besides  mauveine,  there  are  two  other  compounds,  one 
possessing  a  redder  shade  of  colour,  the  other  being  remarkable 
for  its  great  solubility  in  alcohol.  This  latter  from  analysis 
appears  to  have  the  formula  C^H^N^ 

The  first  product,  or  mauveine,  is  evidently  a  derivative  of 
paratoluidine  and  aniline.  The  second  of  orthotoluidine  and 
aniline,  and  the  third  of  pure  aniline.  This  has  been  called 
pseudo-mauveine.  It  might  perhaps  be  better  called  pheno- 
mauveine. 

When  boiled  with  aniline  mauveine  yields  an  indigo-blue 
product,  difficultly  soluble  in  alcohol.  This  change  takes  place 
without  formation  of  ammonia,  and  shows  how  different 
mauveine  is  in  its  character  to  rosaniline. 

Runge  found  that  aniline,  when  treated  with  dilute  chloride 
of  lime,  yielded  a  blue-  or  violet-coloured  solution,  which  soon 
underwent  change.  Some  experiments  on  this,  made  in  1868 
(Jour.  Chem.  Soc.,  xxii.  25-27),  showed  that  the  product  which  I 
named  "  Runge's  blue"  was  a  peculiar  compound,  the  salt  of 
an  organic  base,  which  itself  dissolved  in  alcohol  with  a  reddish- 
brown  colour,  the  salts  being  blue.  It  is  quite  different  from 
mauveine,  and  of  no  practical  value  ;  but  what  is  interesting  is 
that  when  exposed  to  heat,  as  by  boiling  a  solution  of  one  of 
its  salts,  it  decomposes  with  formation  of  mauveine. 

A  beautiful  colouring  matter  was  obtained  from  mauveine 
by  treating  it  with  ethyl  iodide.  It  gives  shades  of  colour  of 
a  very  red  purple  tint,  and  it  was  therefore  called  dahlia.  It 
was  mostly  used  in  calico  delaine  and  other  kinds  of  printing, 
but  being  costly,  the  production  was  never  very  large.  This 
substance  is  a  monoethyl  derivative  of  mauveine,  and  all 
attempts  to  further  ethylate  this  compound  have  proved  fruitless. 
In  properties  it  appears  to  be  more  like  an  ammonium  compound 
than  a  displacement  product. 

SAFRANINES 

In  the  preparation  of  mauveine,  a  colouring  matter  was 
obtained  from  the  liquors,  from  which  it  was  precipitated, 


8o  THE   BRITISH   COAL-TAR   INDUSTRY 

yielding  beautiful  crimson-red  shades  of  colour  on  silk.  The 
amount  produced  in  this  was  so  small,  however,  that  we  were  not 
able  to  introduce  it  as  a  dye.  But  it  was  found  that  it  could  be 
produced  by  the  oxidation  of  the  mauve  dye  itself,  and  was 
then  manufactured  under  the  name  of  "aniline  pink,"  but 
afterwards  "  safranine."  This  substance  is  evidently  closely 
related  to  mauveine,  as  it  gives  the  characteristic  reaction  with 
sulphuric  acid  I  have  already  referred  to. 

The  preparation  of  this  from  the  mauve  dye  was  too  costly 
to  allow  of  its  being  brought  into  general  use.  However,  new 
processes  have  been  since  discovered,  by  which  this  and  other 
colouring  matters  of  its  class  can  be  produced  cheaply. 

The  first  of  these  processes  consisted  in  passing  nitrous  acid 
into  commercial  aniline,  heating  the  mixture  with  arsenic  acid, 
and  then  extracting  the  colouring  matter  produced.  Hofmann 
examined  this,  and  showed  that  it  had  the  formula  C2iH2oN4 
(Ber.,  vi.  526,  1872). 

By  examination  of  the  product  which  was  obtained  by 
oxidising  the  mauve  dye  I  found  it  to  have  the  composition 
C2oH18N4  (Jour.  Chem.  Soc.,  xxxv.  731),  results  which  correspond 
with  analyses  published  by  Dale  and  Schorlemmer  (Jour.  Chem.  Soc., 
xxxv.  682)  obtained  from  the  examination  of  a  similar  product. 
This  substance,  I  also  found,  was  associated  with  that  examined 
by  Hofmann  in  a  product  prepared  by  Messrs  Guinon  &  Co., 
of  Lyons. 

Methods  of  a  more  synthetical  nature  have  since  then  been 
discovered.  O.  Witt  found  that  safranine  could  be  obtained  from 
orthoazotoluene  and  hydrochloride  of  toluidine  at  i5O°-2oo°  C. 
(Bcr.,  x.  874,  1877).  He  then  found  that  by  oxidising  a 
mixture  of  one  part  of  paraphenylenediamine,  and  two  parts  of 
aniline,  on  the  application  of  heat  a  safranine  could  be  obtained 
which  has  the  formula  C18H16N4,  and  which  is  called  pheno- 
safranine. 

The  formation  of  this  colouring  matter  by  this  and  other 
processes  has  been  studied  by  Nietzki  (Ber.,  xvi.  464).  He 
finds  that  the  aniline  in  the  reaction,  in  which  paraphenylenedia- 
mine takes  part,  may  be  substituted  by  other  primary  monamines, 
or  a  mixture  of  these  with  dimethylaniline,  and  thus  a  large 
number  of  these  dyes  can  be  obtained. 

Phenosafranine  is  now  produced  very  largely,  and  in  a  pure 
crystallised  condition,  and  is  a  very  useful  dyeing  agent. 


COLOURING   MATTERS   FROM    COAL-TAR      81 

If  we  assume  that  all  the  safranines  are  strictly  homologous 
compounds,  the  formula  that  Nietzki  gives  for  phenosafranine 
would  make  the  formula  of  that  examined  by  Hofmann,  and 
that  examined  by  myself  and  Dale  and  Schorlemmer,  to  be 
incorrect,  and  that  they  should  contain  two  hydrogens  more 
than  are  assigned  to  them.  This  I  cannot  think  is  possible  from 
all  the  analytical  results  we  obtained. 

The  constitution  of  mauveine  has  not  yet  been  established, 
and  I  have  still  experiments  on  this  subject  in  hand.  This  may 
also  be  said  of  safranine,  I  think,  although  Nietzki  has  proposed 
a  formula  for  it  in  which  nitrogen  occupies  a  similar  position 
to  the  methane-carbon  in  the  rosaniline  series. 


TRIPHENYLMETHANE  DERIVATIVES 

We  must  now  go  back  again  to  the  early  days  of  this 
industry  to  consider  the  next  class  of  compounds — viz. 
triphenylmethane  derivatives. 

The  industrial  success  of  the  mauve  dye  caused  aniline  to 
become  a  very  favourite  body  to  experiment  with,  and  the  result 
was  that  in  1859  the  discovery  of  that  important  colouring 
matter  first  known  as  fuchsine  or  magenta  took  place.  Hofmann 
had  observed  in  his  experiments  on  the  action  of  carbon  tetra- 
chloride  on  aniline  in  1858  the  formation  of  a  red  colouring 
matter,  which  consisted  of  this  substance  as  a  secondary  product 
of  the  reaction,  but  it  was  M.  Verguin  who  first  discovered  a 
process  for  the  transformation  of  aniline  into  a  red  colouring 
matter  of  tinctorial  value.  The  discovery  of  this  compound 
marks  a  most  important  fresh  departure  in  the  history  of  coal- 
tar  colours.  As  I  mentioned,  the  mauve  had  paved  the  way 
for  future  colouring  matters,  and  this  new  substance,  which  could 
be  applied  to  fabrics  by  the  same  methods  as  the  mauve,  was 
most  eagerly  sought  after  owing  to  the  brilliancy  of  its  colour, 
and  probably  its  manufacture  was  one  of  the  most  successful 
financially  of  all  the  aniline  colours. 

M.  Verguin's  process,  which  consisted  in  treating  commercial 
aniline  with  tin  tetrachloride,  was  soon  superseded  by  better 
processes.  The  number  of  patents  taken  out  for  the  production 
of  this  dye  was  very  large,  and  all  imaginable  products  were 
claimed  as  capable  of  producing  it  from  aniline.  The  two  most 
important,  however,  were  those  in  which  mercury  nitrate  and 

6 


82  THE   BRITISH   COAL-TAR   INDUSTRY 

arsenic  acid  were  used.  The  first  of  these  processes,  with  which 
I  had  some  experience,  required  much  care  to  regulate  the 
reaction  and  prevent  deflagration.  The  next  process  with 
arsenic  acid,  known  as  Medlock's,  was  by  far  the  best,  and  was 
employed  very  extensively  until  the  last  few  years,  nitrobenzene 
being  now  mostly  used  as  the  oxidising  agent  in  the  place  of 
arsenic  acid. 

The  manufacture  of  magenta,  which  at  this  period  was  often 
called  roseine,  was  carried  on  chiefly  in  this  country  by  Messrs 
Simpson,  Maule  &  Nicholson,  by  the  arsenic  acid  process. 
Mr  E.  C.  Nicholson  and  Dr  A.  P.  Price,  of  this  firm,  worked 
out  the  process  with  great  success,  and  were  the  first  to  produce 
this  colouring  matter  in  a  pure  state.  The  beautiful  display 
of  the  crystallised  acetate,  shown  at  the  Exhibition  of  1862, 
illustrated  this  fully. 

It  was  with  products  supplied  by  Mr  Nicholson  that  Dr 
Hofmann  made  his  first  researches  on  this  colouring  matter. 
He  changed  its  name  from  roseine  to  rosaniline,  and  found  that 
the  base,  when  in  combination  with  acids,  had  the  formula 
QoHjgNs. 

The  important  observation  of  Nicholson,  and  the  critical 
experiments  of  Hofmann,  on  the  necessity  of  using,  not  pure 
aniline,  but  a  mixture  of  aniline  and  toluidine  for  the  production 
of  this  substance,  was  made  about  this  period.1 

The  next  important  step  in  this  industry  was  the  use  of 
rosaniline  itself  as  a  source  of  new  colouring  matters.  For 
this  we  are  indebted  to  the  experiments  of  two  French  chemists, 
viz.  MM.  Girard  and  De  Laire,  who  discovered  that  rosaniline 
salts,  when  heated  with  aniline,  gave  violet  and  blue  colouring 
matters,  which  they  called  violet  imperial  and  bleu  de  Lyon.  It 
is,  however,  to  Mr  Nicholson  that  the  credit  of  producing 
these  bodies,  in  a  practically  pure  state,  belongs.  This  especially 
refers  to  the  blue,  the  product  known  as  opal  blue,  used  by 
Dr  Hofmann  in  his  investigations  on  the  subject,  being  of  great 
purity.  Dr  Hofmann  showed  that  these  products  were  phenyl- 
ated  rosanilines,  as  is  now  well  known,  ammonia  being  given  off 

1  In  my  original  patent  it  was  shown  that  colouring  matters  could  be 
obtained  not  only  from  aniline,  but  also  from  toluidine,  xylidine,  and 
cumidine — these  bases,  as  usually  prepared  at  that  date  from  the  hydro- 
carbons obtained  by  fractioning  coal-tar  naphtha,  not  being  pure,  but 
mixtures. 


COLOURING   MATTERS   FROM    COAL-TAR      83 

in  the  reaction.  And  I  may  mention  in  passing  that  the  manu- 
facture of  these  blues  is  now  carried  on  to  such  a  large  extent 
that  the  ammonia  produced  in  this  reaction  is  collected  for  the 
production  of  its  sulphate  or  other  salt. 

One  of  the  difficulties  in  the  way  of  the  new  blue  was  its 
insolubility  in  water.  Mr  Nicholson,  however  (in  1862), 
probably  thinking  of  the  method  used  to  render  indigo  soluble, 
experimented  upon  the  action  of  sulphuric  acid  on  this  com- 
pound, and  he  found  that  it  was  possible  to  obtain  sulphonic 
acids  from  it.  One  of  these,  the  sodium  salt  of  which  is 
known  as  Nicholson's  or  alkali  blue,  is  the  monosulphonic  acid, 
which  is  itself  insoluble  in  water,  but  forms  soluble  salts,  which 
can  be  applied  to  the  goods,  and  then  decomposed  by  acids. 
This  compound  has  had  much  to  do  with  the  successful  intro- 
duction of  this  colouring  matter.  The  other  product  known  as 
soluble  blue  is  the  sodium  salt  of  the  trisulphonic  acid. 

In  the  early  part  of  1864  the  Hofmann  violets  were  intro- 
duced. These,  as  is  well  known,  are  the  ethylated  rosanilines 
produced  by  acting  upon  rosaniline  with  ethyliodide.  These 
colouring  matters  are  more  brilliant,  though  much  more  fugi- 
tive than  mauveine  ;  but  by  this  time  the  desire  for  per- 
manency was  giving  way  very  much  to  that  of  brilliancy  ;  and 
these  colouring  matters  were  quickly  taken  up  by  dyers  and 
calico  printers. 

About  this  time  some  colouring  matters  derived  from  phenol 
were  introduced,  and  which,  curiously,  are  found  to  belong  to 
the  class  of  substances  now  under  consideration.  These  were 
brought  forward  by  Messrs  Guinon,  Marnas  &  Bonnet,  of 
Lyons.  The  first  product  was  aurin,  prepared  from  phenol  by 
means  of  oxalic  and  sulphuric  acid  (Kolbe  and  Schmitt's  process). 
The  next  was  peonine,  obtained  by  acting  upon  aurin  with 
ammonia.  The  third  was  azuline,  prepared  by  heating  aurin 
with  aniline.  This  last  was  a  blue  dye,  which  has  since  been 
shown  to  consist  chiefly  of  triphenylrosaniline. 

Purple  and  violet  derivatives  were  also  obtained  from 
rosaniline  by  a  process  of  my  own,  in  which  brominated 
turpentine  was  employed.  These  were  known  as  Britannia 
violets,  and  were  much  used. 

Other  coloured  derivatives  were  also  discovered ;  for  example, 
by  the  action  of  aldehyde  and  sulphuric  acid,  a  blue  product 
was  obtained,  which,  when  treated  with  sodium  hyposulphite 


84  THE   BRITISH   COAL-TAR   INDUSTRY 

or  sulphuretted  hydrogen  water,  yielded  the  well-known  aldehyde 
green. 

On  examining  the  action  of  acetylchloride  on  Britannia  violet, 
I  obtained  a  peculiar  green,  which  was  used  principally  by  calico 
printers,  and  very  considerable  quantities  of  acetylchloride  were 
prepared  for  this  purpose.  The  process  was  not  published. 
This  green  was  of  a  blue  shade,  and  was  obtained  in  a  crystallised 
condition  in  combination  with  picric  acid.  The  crystals  had  a 
golden  metallic  reflection. 

Soon  after  this  it  was  noticed  that  a  green  compound  was 
produced  in  the  preparation  of  the  Hofmann  violets,  though 
generally  only  in  small  quantities.  It  was  afterwards  found  that 
by  making  rosaniline  react  with  an  excess  of  methyl  iodide 
it  could  be  produced  practically.  It  was  called  iodine  green  ; 
but  the  product  now  manufactured  is  a  chloride.  This  colour- 
ing matter  gave  good  candlelight  greens.  One  of  its  peculiarities 
is  that  when  heated  it  is  converted  into  violet  methylrosaniline, 
with  loss  of  methylchloride. 

A  new  method  of  producing  rosaniline  violet  was  proposed 
by  Lauth,  and  patented  by  MM.  Porrier  &  Chappat,  in  June 
1866.  The  process  consisted  in  taking  aniline,  in  which 
hydrogen  had  been  replaced  by  an  alcohol  radical,  and  oxidising 
this  instead  of  first  preparing  rosaniline,  and  then  replacing  the 
hydrogen  in  the  colouring  matter  by  the  radical.  The  product 
proposed  for  this  purpose  was  methylaniline. 

Owing  to  the  improved  method  of  methylating  aniline, 
which,  I  believe,  was  first  proposed  by  Messrs  Girard  and 
De  Laire  (Bull.  Chem.  Soc.  [2],  vii.  360),  this  process  has  become 
a  very  important  one,  and  large  quantities  of  dimethylaniline 
are  now  used,  the  oxidation  being  effected  by  copper  salts.  The 
product,  according  to  the  researches  of  Otto  Fischer,  consists 
chiefly  of  pentamethylpararosaniline. 

The  most  important  advance  in  the  production  of  green 
colouring  matters  of  the  triphenylmethane  series  was  the  dis- 
covery of  the  benzaldehyde,  Victoria,  or  malachite  green. 

In  1877,  Otto  Fischer,  whilst  investigating  the  condensation 
products  of  tertiary  aromatic  bases  (Eer.^  x.  1625),  obtained  by 
the  action  of  benzaldehyde  on  dimethylaniline  in  presence  of 
chloride  of  zinc,  a  colourless  base  of  the  formula  C23H26N2,  the 
salts  of  which,  when  exposed  to  the  air,  rapidly  oxidised  to  a 
fine  blue-green  dyestuff,  which,  he  thought,  would  prove  to  be 


COLOURING   MATTERS   FROM   COAL-TAR      85 

of  complicated  constitution.  A  little  later  (Ber.y  xi.  950)  he 
showed  that  by  treating  this  colourless  base  with  some  of  the 
ordinary  oxidising  agents,  this  green  could  be  more  easily 
produced,  and  that  it  stood  to  the  colourless  compound  in  the 
same  relation  as  rosaniline  does  to  leucaniline.  Emil  and  Otto 
Fischer  afterwards  said  (Ber.,  xii.  796)  that  the  first  experiments 
for  the  production  of  this  green  were  made  by  the  Badische 
Anilin-  und  Soda-Fabrik,  in  March  1878.  About  this  time 
Oscar  Doebner  (Eer.^  xi.  950)  found  that  a  green  colouring 
matter  was  produced  by  heating  benzaldehyde  with  benzoyltri- 
chloride  and  zinc  chloride.  This  product  has  been  found  to  be 
identical  with  that  of  Fischer's.  This  green  colouring  matter 
is  now  largely  made  from  benzaldehyde,  as  this  process  is  found 
to  be  the  best.  A  similar  compound  is  also  prepared  from 
diethylaniline,  and  is  known  as  brilliant  green.  It  is  a  beauti- 
fully crystalline  body.  It  is  rather  curious  that  this  produces 
shades  of  colour  somewhat  yellower  than  the  green  from 
dimethylaniline,  whereas,  being  of  a  higher  molecular  weight, 
we  should  have  expected  it  to  be  bluer. 

The  principal  difficulty  which  had  to  be  contended  with  in 
the  production  of  these  colouring  matters  was  the  need  of  a 
supply  of  benzaldehyde.  The  usual  method  of  obtaining  it 
from  bitter  almonds,  which  was  the  only  one  in  use,  was  quite 
out  of  the  question,  so  that  other  sources  had  to  be  looked  for. 
The  Badische  Anilin-  und  Soda-Fabrik,  however,  successfully 
overcame  this  difficulty.  At  first  they  experimented  with  the 
process  of  Lauth  and  Grimaux,  which  consists  in  the  oxidation 
of  benzylchloride,  with  an  aqueous  solution  of  lead  nitrate  ;  the 
product  made  by  this  process,  however,  was  too  dear.  But  they 
found  that  the  decomposition  of  benzylidenedichloride,  by  means 
of  water,  as  observed  by  Cahours  (Ann.  Chem.  SuppL,  ii.  306)  and 
Limpricht  (Ann.  Chem.,  139,  316),  gave  them  a  means  of  produc- 
ing this  compound  practically,  the  reaction  being  as  follows  : 

C6H5CHC12  +  OH2  =  C6H5.CHO  +  2HC1. 

This  process,  which  they  have  successfully  employed  since 
March  1878,  consists  in  the  preparation  of  benzylidenedichloride 
from  pure  toluene,  and  in  the  subsequent  treatment  of  this 
chlorinated  body  with  milk  of  lime,  at  100°  C. 

I  have  stated  that  the  group  of  colouring  matters  under 
consideration  are  called  triphenylmethane  derivatives,  and  to 


86  THE   BRITISH   COAL-TAR   INDUSTRY 

show  how  this  has  been  proved  to  be  the  case,  I  must  now  refer 
very  briefly  to  some  of  the  theoretical  work  which  has  led  to 
this  knowledge.  The  most  important  of  this  refers  to  rosaniline. 
I  have  already  drawn  attention  to  the  work  of  Hofmann,  which 
gave  us  the  first  knowledge  of  the  composition  of  this  colouring 
matter,  and  the  further  information  that  it  contained  hydrogen, 
which  could  be  displaced  by  phenyl  and  alcohol  radicals  ;  but 
as  to  the  matter  of  constitution,  I  think  the  experiments  of 
Caro  and  Wanklyn  were  the  first,  as  they  showed  the  relation 
which  existed  between  rosaniline  and  aurin,  or  rosolic  acid,  and, 
in  fact,  they  produced  rosolic  acid  from  rosaniline  ;  but  it  is  to 
the  beautiful  researches  of  Emil  and  Otto  Fischer  that  we  are 
indebted  for  a  clear  knowledge  of  the  constitution  of  this  class 
of  colouring  matter. 

But  to  clear  the  ground  before  proceeding  further,  I  must 
remind  you  that  ordinary  commercial  rosaniline,  or  magenta, 
prepared  from  aniline  and  toluidines,  is  a  mixture  of  colouring 
matters.  This  was  first  known  to  Mr  Nicholson,  who  found 
that  for  the  production  of  the  finest  blues  it  was  necessary  to 
purify  the  base  and  separate  one  of  these  before  phenylating  ; 
but  it  is  only  of  later  years  that  the  difference  between  these 
bodies  has  been  carefully  studied  and  explained.  The  base 
examined  by  Hofmann  contained  C2o,  and  is  the  chief  constituent 
of  commercial  rosaniline.  The  other  contains  C19,  and  is  now 
called  pararosaniline,  because  it  is  produced  from  aniline  and 
paratoluidine.  Similarly,  in  commercial  aurin,  two  compounds 
are  found,  one  containing  C^,  now  called  rosolic  acid,  and  one 
containing  C19,  now  called  aurin  ;  and  these  latter  can  be  pro- 
duced from  the  corresponding  rosanilines  ;  and  Dale  and  Schor- 
lemmer  have  shown  that  aurin  can  be  also  converted  into  para- 
rosaniline by  the  action  of  ammonia  (Jour.  Chem.  Soc., 
xxxii.  121). 

Emil  and  Otto  Fischer,  however,  by  submitting  the  leuco 
compound  of  commercial  rosaniline  to  the  diazo  reaction, 
obtained  the  hydrocarbon  C20H18,  and  from  rosaniline  prepared 
from  paratoluidine  and  aniline  the  hydrocarbon  C19H16. 

And  this  latter  hydrocarbon  was  found  to  be  identical  with 
Kekule's  triphenylmethane — 


COLOURING    MATTERS   FROM    COAL-TAR      87 

On    nitrating    this    hydrocarbon,    they   obtained   a   trinitro 
derivative,  which,  when  reduced,  gave  the  triamido  body, 

NH2C6H4,         xC6H4NH2 
[/      ^H 


NH2C6H, 


which  is  paraleucaniline,  and  by  carefully  heating  its  hydro- 
chloride  to  1 50°- 1 60°  C.,  it  was  converted  into  pararosaniline. 

Also  they  found  that  by  oxidising  trinitrotriphenylmethane 
they  obtained  trinitrotriphenylcarbinol,  and  this  when  reduced 
gave  pararosaniline  direct. 

From  these  results  the  constitution  of  the  base  is  evidently 

NH2C6H4V      yC6H4NH2 


NH2C6H 

Pararosaniline 


the  salts — the  hydrochloride,  for  example — being 

NH2CCH4V    /C6H4NH.HC1 
>C  I 


NH2C61 


Pararosaniline  hydrochloride. 

Similar   results  were    obtained   from    the  hydrocarbon  from 
rosaniline  ;  it  is  tolyldiphenylmethane  : 


The  rosolic  acid  and  aurin  corresponding  to  the  rosanilines 
are  constituted  in  an  analogous  manner  : 


HOC6H4\     /C6H4O  HOC6H3(CH3)v      /C6H4O 

>C_      _J      and  >C  I 

HOC«H/  HOC, 


> 

H/ 


'6J 
Aurin.  Rosolic  acid. 

From  these  results  we  see  the  beautiful  relationships  of  the 
various  colouring  matters  of  this  series  to  each  other,  and  by  it 
obtain  information  which  is  of  practical  value;,  as  well  as 
theoretical.  The  following  formulae  of  a  few  of  these  products 
further  illustrate  this  : — 

H\    /H 

Methane  (Marsh  Gas)       >C< 

H/      XH 


88  THE   BRITISH   COAL-TAR   INDUSTRY 


Triphenylmethane 

C  1 

H2NC6H4v       /C6H4NH2 


n2^en4\       /^ 

Leucopararosaniline  /C\ 

H2NC6H/     \H 

H2NC6H4v         ,C6H4NH2 
Pararosaniline  /C\ 

H2NC6H/       XOH 

.,.      H2NC6H4V       /C6H4NH.HC1 

Pararosaniline     2  \r/  I 

hydrochloride  H2NC6H4< 


L2 

Triphenylpara- 


rosaniline 
hydrochloride 
(Aniline  Blue) 


H(C6H5)NC6H4V      /C6H4N(C6H5)H 
H(C6H5)NC6H4< 


Hexamethylpara-  |  (CH3)2NC6H4sv^       xC6H4N(CH3)2Cl 

rosaniline         >  /^   ' 

(Methyl  Violet)  )  (CH3)2NC6H/ 

(CH3)2NC6H4X     /C6H4N(CH3)2C1 

Methyl  Green  >C^- ' 

C1(CH8)3NC6H/ 

Benzaldehyde  (CH3)2NC6H4V      /C6H4N(CH3)2C1 

or  j>C^- ' 

Victoria  Green  QH/ 

(C2H5)5NC6H4V     /C6H4N(C2H5)2C1 

Brilliant  Green  >C^- ' 

r  TT  / 

^6^6 

NaSO3  )  r  w  r  w  /  NaSO3 

H(C6H5)N  f  C6W3\  Utl3 1  N(C6H5) 


Soluble  Blue  ^- 

NaS03 


The  effect  of  displacing  hydrogen  by  hydrocarbon  radicals  in 
rosaniline  is  seen  to  result  in  the  shade  of  colour  becoming  bluer 
for  each  hydrogen  displaced  —  the  effect  of  those  of  high  molecular 
weight,  such  as  phenyl,  being  to  produce  the  greatest  change  ; 
thus  triphenylrosaniline  is  blue,  whilst  hexamethylrosaniline  is 
blue  violet,  notwithstanding  it  contains  six  hydrogens  displaced. 

After  all  the  displacements  possible  have  been  effected,  as 
in  hexamethylrosaniline,  the  result  of  the  combination  of  the 


COLOURING   MATTERS   FROM    COAL-TAR      89 

products  with  halogen  compounds  of  methyl  is  very  interesting. 
The  particular  group  to  which  this  is  attached  becomes  of  the 
nature  of  an  ammonium  group,  and  the  colour  does  not  become 
bluer,  but  changes  to  green — i.e.  methyl  green, — and  this,  like 
other  ammonium  compounds,  when  heated,  dissociates  with  loss 
of  the  halogen  compound  of  methyl,  and  then  hexamethylros- 
aniline  is  reproduced.  Again,  if  this  ammonium  group  be  sub- 
stituted by  phenyl,  we  also  get  a  green  product — i.e.  Victoria 
green. 

The  structure  of  some  of  these  bodies  has  been  proved  by 
another  most  beautiful  synthetical  process,  which  has  lately 
come  into  use — a  process  which  enables  us  now  not  only  to 
say  that  we  employ  the  volatile  products  of  the  distillation  of 
coal,  but  also  the  coke  itself  ;  as  carbonic  oxide  in  combination 
with  chlorine  (phosgene,  or  carbon  oxychloride)  is  one  of  the 
important  agents  used.  This  substance  was  discovered  in  1812 
by  J.  Davy. 

In  1876,  W.  Michler  gave  an  account  of  his  researches  on 
the  synthesis  of  aromatic  ketones  by  means  of  phosgene 
(Ber.y  ix.  7 1 6),  in  which  he  showed  by  the  action  of  this  substance 
on  dimethylaniline  that  a  tetramethylated  diamidobenzophenone 
was  obtained.  This  substance  has,  therefore,  the  constitution 

N(CH3)2C6H4  -  CO  -  C6H4(CH3)2N. 

The  formation  of  this  product  takes  place  in  two  phases,  but  I 
need  not  enter  into  that  now. 

The  first  experiments  to  turn  Michler's  synthetically  prepared 
tetramethylated  diamidobenzophenone  to  practical  account  were 
made  by  Dr  A.  Kern,  in  the  works  of  Bindschedler,  at  Basle. 
Dr  Kern  proved  that  an  agent  like  phosgene  might  be  produced 
on  a  larger  scale,  and  he  invented  a  process  to  convert  Michler's 
ketone  base  into  methyl  purple.  This  process  was  derived  from 
the  ketone  synthesis  of  triphenylmethane  from  benzhydrol 
and  benzene,  and  consisted  in  preparing  the  tetramethyldiamido- 
benzhydrol,  and  condensing  the  latter  with  dimethylaniline  ; 
thus  the  leuco  base  of  hexamethylrosaniline  was  obtained,  and 
then  oxidised  with  lead  peroxide.  This  process,  which  was  too 
costly  for  practical  purposes,  has  been  superseded  by  one 
discovered  by  Dr  Caro,  who  has  found  that  this  ketone  base 
can  be  made  to  form  condensation  products  with  dimethylaniline 
and  other  products  directly,  by  the  use  of  phosphorus  tri- 


90  THE   BRITISH   COAL-TAR   INDUSTRY 

chloride — this  substance  converting  it  first  into  a  chloride,  which 
then  reacts  on  the  dimethylaniline,  thus — 

N(CH3)2C6H4  -  CC12  -  C6H4(CH3)2N  +  N(CH3)2C6H5 

N(CH3)2C6H4V      /C6H4(CH3)2N,C1 


+  HC1 

N(CH3)2C6H/ 

And  this  reaction  takes  place  quantitatively,  the  body  being  so 
pure  that  it  readily  crystallises  from  water  in  prisms,  like 
potassium  permanganate,  only  with  a  very  much  more  brilliant 
lustre.  These  contain  water  of  crystallisation.  The  condensa- 
tion can  also  be  effected  with  phosgene  gas.  The  colouring 
matter  obtained  by  this  means  is  bluer  than  that  obtained  from 
dimethylaniline  by  oxidation,  which  consists  chiefly  of  the 
pentamethyl  compound.1 

Diethylene  can  also  be  made  into  a  ketone  with  phosgene 
or  carbon  oxychloride,  and  this  product  condensed  with  diethyl- 
aniline  yields  hexaethylpararosaniline. 

Instead  of  dimethylaniline,  dimethyl-a-naphthylamine  can 
be  used,  and  in  this  case  a  beautiful  blue  colouring  matter  is 
obtained,  and  if  a-phenylnaphthylamine  be  employed,  the 
Victoria  blue  is  produced,  and  by  varying  the  reaction  in  this 
kind  of  way  a  great  variety  of  colouring  matter  can  be 
synthetically  prepared. 

With  ammonia  this  ketone  condenses  to  form  the  new  yellow 
colouring  matter,  auramine,  with  aniline  phenylauramine.  With 
quinoline  it  produces  a  green  very  similar  to  Victoria  or  benzalde- 
hyde  green.  I  must  not,  however,  spend  any  more  time  over 
this  interesting  part  of  the  subject,  but  may  say  here  again  we 
have  pure  scientific  research  conducted  for  its  own  sake,  bearing 
fruit.  The  discovery  of  W.  Michler,  which  remained  for  seven 
years  a  matter  of  theoretical  interest,  now  comes  forward  as  a 
matter  of  practical  value. 

ANTHRAQUINONE  SERIES 

I  must  now  draw  your  attention  to  the  important  class 
of  colouring  matter  compounds  obtained  from  anthracene  or 
anthraquinone. 

1  See  Caro,  Eng.  Patents,  4428,  September  1883;  4850,  i3th  March 
1884;  and  5038,  i8th  March  1884. 


COLOURING   MATTERS   FROM    COAL-TAR      91 

Alizarin  and  the  other  colouring  matters  related  to  it  form 
one  of  the  most  important  branches  of  the  coal-tar  colour 
industry,  and  one  of  special  interest,  because  alizarin  was  the 
first  instance  of  the  production  of  a  natural  colouring  matter 
artificially.  It  will  be  quite  unnecessary  for  me  here  to  say 
much  about  the  madder-root,  which  was  the  original  source 
of  alizarin,  and  was  grown  in  such  enormous  quantities,  but 
now  is  nearly  a  thing  of  the  past ;  nor  will  I  enter  into  the  early 
chemical  history  of  alizarin,  and  all  the  laborious  work  which 
was  bestowed  upon  it  by  Dr  Schunck  and  others.  As  you  are 
probably  all  aware,  the  relationship  of  alizarin  and  its  formation  from 
the  coal-tar  hydrocarbon  anthracene  was  the  result  of  the  labours 
of  Graebe  and  Liebermann,  the  researches  which  culminated 
in  this  being  of  a  purely  scientific  nature.  The  original  process 
for  obtaining  it  has,  however,  not  been  found  of  practical  value, 
but  a  new  one  in  which  sulphuric  acid  could  be  used  in  place 
of  bromine  was  afterwards  discovered  by  Caro,  Graebe  and 
Liebermann  in  Germany,  and  by  myself  in  this  country, 
apparently  simultaneously.  A  second  process  was  also  dis- 
covered by  me  which  was  worked  nearly  all  the  time  I  was 
engaged  in  this  industry.  In  this,  dichloranthracene  was  used 
instead  of  anthraquinone,  and  the  product  thus  obtained  yielded 
colours  of  a  brilliancy  which  it  has  been  found,  even  to  the 
present  time,  difficult  to  match  by  the  anthraquinone  process. 

At  the  time  of  the  discovery  of  artificial  alizarin,  anthracene 
was  not  prepared  by  the  tar  distillers,  as  it  had  no  application, 
and  very  little  was  known  about  it.  It  was  discovered  in  1832 
by  Dumas  and  Laurent.  In  1854—55,  when  studying  under 
Dr  Hofmann,  I  worked  with  it  for  some  time,  but  my  results 
were  never  published,  because,  owing  to  the  erroneous  formula 
given  to  it  by  Dumas  and  Laurent,  which  was  accepted,  my 
results  would  not  fit  in  ;  nevertheless  the  information  obtained 
afterwards  proved  of  great  value  to  me,  although  at  the  time 
the  labour  spent  appeared  to  be  lost  labour,  showing  the  value 
of  research  even  when  not  successful.  The  formula  of  this 
hydrocarbon  was  not  established  until  1862,  when  it  was  studied 
by  Dr  Anderson.  This  was  only  six  years  before  the  discovery 
of  Graebe  and  Liebermann,  and,  had  not  the  formula  of 
anthracene  been  established  before  these  chemists  commenced 
their  work,  the  relationship  of  alizarin  to  it  would  not  have 
been  discovered,  and  up  to  this  day  it  is  possible  that  this 


92  THE   BRITISH   COAL-TAR   INDUSTRY 

artificial  alizarin  industry  would  not  have  been  in  existence. 
Researches  like  that  of  Dr  Anderson  I  have  often  heard  spoken 
of  slightingly,  because  they  don't  bear  much  on  their  surface  ; 
but  who  knows  what  such  work  may  lead  to  ?  Earnest  workers 
cannot  be  too  much  encouraged. 

As  anthracene  was  not  a  commercial  product,  it  was  necessary 
to  experiment  on  its  production  before  alizarin  could  be 
manufactured,  and  not  only  on  the  best  methods  of  getting  it, 
but  also  to  get  a  rough  idea  of  how  much  could  be  produced, 
because  unless  the  hydrocarbon  could  be  obtained  in  large 
quantities,  artificial  alizarin  could  not  compete  with  madder. 
In  our  works  at  Greenford  Green  we  commenced  by  distilling 
pitch  ;  but  afterwards  tar  distillers  were  induced  to  try  to 
separate  it  from  the  last  runnings  of  their  stills  by  cooling 
and  then  filtering  off  the  crystalline  products  which  separated 
out,  and  in  fact  visits  were  paid  to  most  of  the  tar  distillers 
of  the  United  Kingdom,  others  being  corresponded  with  on 
the  subject,  and  the  result  was  that  in  a  short  time  such 
quantities  came  in  that  the  distillation  of  pitch  was  abandoned. 
And  although  much  doubt  and  anxiety  prevailed  at  first  as  to 
the  possibility  of  getting  a  sufficient  supply  of  this  raw  material, 
two  or  three  years  since  there  were  about  1000  tons  of  com- 
mercial anthracene  (about  30  per  cent.)  produced  in  excess  of  the 
requirements,  the  annual  production  HI  the  United  Kingdom 
being  estimated  at  about  6000  tons  30  per  cent.,  or  nearly  2000 
tons  pure  anthracene. 

Although  the  colouring  matter  obtained  from  anthraquinone 
or  dichloranthracene  was  at  first  simply  considered  as  alizarin 
more  or  less  pure,  yet  on  investigating  the  matter  it  was  soon 
found  that  it  contained  other  colouring  matter.  To  this  I  drew 
attention  in  1870  (Jour.  Chem.  Soc.y  xxiii.  143,  footnote),  and  in 
1872  gave  the  analysis  of  a  product  which  I  named  anthra- 
purpurin,  followed  by  a  more  extended  account  a  year  after- 
wards (Jour.  Chem.  Soc.,  xxv.  659,  and  xxvi.  425).  It  was  called 
anthrapurpurin  because  it  is  an  anthracene  derivative  having 
the  formula  of  purpurin,  with  which  it  is  isomeric.  In  the  latter 
paper  I  also  referred  to  another  colouring  matter  dyeing  alumina 
mordants  of  an  orange  colour  (Jour.  Chem.  Soc.y  xxvi.  425). 
It  was  also  shown  that  anthraflavic  acid  when  fused  with  alkali 
gave  a  colouring  matter  behaving  with  mordants  in  the  same 
way  (Jour.  Chem.  Soc.y  xxvi.  26]  and  this  has  proved  to  be  the 


COLOURING    MATTERS   FROM    COAL-TAR      93 

same  body.  This  latter  reaction  was  afterwards  more  fully 
studied  by  Schunck  and  Roemer,  and  the  colouring  matter 
produced  by  it  was  shown  also  to  have  the  formula  of  purpurin  ; 
they  therefore  called  it  flavopurpurin  (Ber.,  ix.  678),  so  that  the 
colouring  matters  formed  have  proved  to  be  three  in  number — 
alizarin,  anthrapurpurin,  and  flavopurpurin,  all  of  which  are 
valuable  dyes,  whereas  in  madder-root  there  is  only  alizarin 
and  purpurin,  the  latter  being  of  but  secondary  value.  This 
can  now  also  be  produced  from  anthracene.  The  researches 
which  have  been  made  on  the  subject  of  the  conditions  under 
which  these  different  colouring  matters  are  formed,  have  led 
to  the  discovery  of  methods  for  their  separate  production,  so 
that  in  artificial  alizarin,  which  name  commercially  embraces 
all  these  colouring  matters,  both  mixed  and  separate,  we  have 
more  than  a  simple  replacer  of  madder-root,  and  as  these 
colouring  matters  just  referred  to  can  be  applied  with  the  same 
mordants,  varieties  of  styles  of  work  can  be  produced  by  the 
calico  printer  and  dyer  which  before  were  unknown.  Anthra- 
purpurin is,  1  believe,  of  as  great  importance  as  alizarin  itself, 
and  used  with  it  increases  its  brilliancy,  and  alone  gives  very 
brilliant  scarlet  shades. 

Artificial  alizarin  was  first  produced  commercially  in  this 
country  by  my  firm  at  Greenford  Green  in  1869,  when  i  ton  was 
produced  ;  in  1870,  40  tons  were  made  ;  in  1871,  220  tons,  and 
so  on  increasingly.  It  was  not  produced  on  the  Continent 
until  1871,  when,  according  to  Graebe  and  Liebermann,  125-150 
tons  were  made.  These  weights  do  not  apply  to  dry  colour, 
but  to  paste. 

I  cannot  go  into  any  lengthened  account  of  the  chemistry  of 
this  industry  here  ;  its  development,  however,  has  kept  pace 
with  theoretical  investigations,  in  some  cases  it  may  be  said  to 
have  forestalled  it.  For  example,  in  the  old  methods  of  working, 
more  anthrapurpurin  than  alizarin  was  produced  ;  the  conditions 
required  to  modify  this  were  found  out  by  experiment. 
According  to  all  our  previous  knowledge  as  to  the  introduction 
of  hydroxyl  into  a  body  by  the  fusion  of  its  sulphonic  acid  with 
alkali,  a  monosulphonic  acid  should  give  a  monohydroxyl  com- 
pound, and  a  disulphonic  acid  a  dihydroxyl  compound.  There- 
fore to  produce  alizarin,  which  is  a  dihydroxyl  compound,  an 
anthraquinone  disulphonic  acid  was  thought  to  be  the  proper 
thing  to  use.  By  experience  this  was  gradually  found  to  be 


94  THE   BRITISH   COAL-TAR   INDUSTRY 

incorrect,  a  monosulphonic  acid  being  required  to  produce 
alizarin,  a  disulphonic  giving  anthra  or  flavopurpurin,  the 
colouring  matter  not  being  due  to  the  primary  but  to  a  secondary 
reaction,  as  was  afterwards  shown  by  research — the  mono  and 
dioxyanthraquinones  (the  latter  known  as  anthraflavic  and 
isoanthraflavic  acids)  being  the  first  products  of  the  reaction,  and 
then  undergoing  oxidation  by  the  caustic  alkali  employed, 
yielding  the  corresponding  colouring  matter,  a  portion  of  the 
products,  however,  being  at  the  same  time  reduced  back  to 
anthraquinone. 

A  very  important  improvement  preventing  this  loss  by 
reduction  was  discovered  by  J.  J.  Koch,  who  found  it  might  be 
avoided  by  the  use  of  a  small  quantity  of  potassium  chlorate 
with  the  alkali  used  in  the  fusion. 

The  amount  of  caustic  soda  used  in  this  industry  is  very 
large,  and  at  the  Badische  Anilin-  und  Soda-Fabrik — and,  I 
believe,  elsewhere — it  is  made  on  the  spot ;  and  I  must  say  the 
cleanly  way  in  which  alkali  is  made  in  the  above  works  contrasts 
very  favourably  with  what  I  have  seen  in  some  of  the  alkali 
works  in  this  country. 

Like  rosaniline,  alizarin  has  now  become  a  material  for  pre- 
paring other  colouring  matters.  Of  these  there  are  two  in 
use — viz.  nitroalizarin,  which  gives  orange-yellow  shades  with 
alumina  mordants,  and  alizarin  blue,  a  remarkable  compound 
prepared  from  nitroalizarin  by  treating  it  with  sulphuric  acid  and 
glycerol.  This  gives  shades  of  colour  like  indigo.  When  first 
discovered,  considerable  difficulty  was  found  in  its  application 
on  account  of  its  insolubility  ;  it  has  since  been  found  to  form 
a  soluble  compound  with  sodium  bisulphite,  and  by  this  means 
its  application  has  become  much  easier.  The  constitution  of 
the  colouring  matter  derived  from  anthracene  may  be  represented 
as  follows  : — 

yCOv  /OH*1' 

Alizarin  C6H4<         >C6H2< 

\:CX  '  X)H(2> 

C( 


/ 
Purpurin  CflH4<  /^g..^-^**. 

XXX  X)H<4) 

/CCX  yOH(1) 

Anthrapurpurin  (m)HO— C6H«<          >C(5H2< 

/  \OH(2) 


COLOURING   MATTERS   FROM    COAL-TAR      95 

/COv  /OH'1' 

Flavopurpurin   °>HO— C6H3<T         >C6H2< 

\rn/  \< 


OH<2> 


XV_,^K  xV^nv ' 

Alizarin  Orange  C6H4<         >C6H4OH'2' 
^CO/          NNO2<3 

/COv  yOH<1J 

Alizarin  Blue  C6H4<^ 


1(4) 

CH=CH-CH 

Those  colouring  matters  under  the  name  of  artificial  alizarin 
are  the  most  important  of  the  coal-tar  colours,  their  money  value 
amounting  to  more  than  a  third  of  the  entire  value  of  all  the 
colours  produced  in  this  industry,  and  at  present  the  price  of 
artificial  alizarin  compared  tinctorially  is  not  more  than  one-fourth 
of  that  of  madder  or  garancine  before  their  production.  There 
are  now  three  works  producing  it  in  this  country,  but  the  bulk 
of  that  used  still  comes  from  Germany. 

PHTHALEINES 

The  discovery  of  this  class  of  bodies  dates  back  to  1871, 
and  was  the  result  of  the  investigation  of  Baeyer.  He  found 
that  phenols  unite  with  a  number  of  polybasic  acids  and  with 
aldehydes,  with  separation  of  water  when  the  mixture  is  heated 
alone,  or  with  glycerol  and  sulphuric  acid,  the  compounds  formed 
not  being  ethers.  Those  produced  when  phthalic  anhydride  is 
employed,  and  which  embrace  those  of  practical  value,  are  called 
phthaleines.  The  first  of  these  discovered  by  Baeyer  was  galle'm 
(Ber.)  iv.  457),  produced  by  heating  pyrogallol  with  phthalic 
anhydride ;  its  formula  is  C2oH14O5  ;  by  reduction  it  loses 
the  elements  of  water  and  combines  with  hydrogen,  forming 
coerulem.  These  colouring  matters,  which  for  a  long  time 
remained  unnoticed,  are  now  being  extensively  used. 

Later,  in  1871,  Baeyer  discovered  resophthalein,  or  fluorescein 
(Ber.,  iv.  555).  This  substance,  which  is  remarkable  for  its 
yellowish-green  fluorescence,  dyes  silk  and  wool  yellow,  but 
does  not  combine  with  mordants,  and  is  not  a  very  useful  dyeing 
agent.  But  it  was  discovered  by  Caro  in  1874,  the  subject  being 
afterwards  worked  out  jointly  with  Baeyer,  that  fluorescein  when 
brominated  yielded  that  beautiful  dyestuff  now  called  cosine  ; 


96 


THE   BRITISH   COAL-TAR   INDUSTRY 


this  was  introduced  into  the  market  in  July  1874.  Other  sub- 
stitution products  were  then  studied,  and  the  iodine  product  was 
found  to  give  bluer  shades  of  red  than  the  bromine  derivative. 
One  of  the  most  beautiful  colours  of  this  series  is  the  dichlor- 
tetraiodofluorescein,  in  the  preparation  of  which  dichlorophthalic 
anhydride  is  used.  It  is  called  phloxine.  The  methylic  ether  of 
eosine  and  its  nitro  derivative  also  have  become  commercial 
articles.  These  bodies  are  now  manufactured  in  a  practically 
pure  condition.  Their  structure  has  been  made  out  by  research 
to  be  as  follows  : — 


Fluorescein 


Eosine.     Tetra-  |   C6H4 
bromofluorescein  >    | 
(Potassium  Salt)  )   C 


CfiH3OH 


C6H3OH 

C6H.Br2(OK) 

I 
O 

C6HBr2(OK) 


Tetraiodofluorescein 
(Potassium  Salt) 


C6HI2(OK) 
i  CAx     /    \ 
}   \COQ/C\  ° 

^C6HI2(OK) 


Phloxine.     Dichloro- )  C6H2C1 
tetraiodofluorescein   V   | 
(Potassium  Salt).      ) 


C6HI2(OK) 
O 
•C6HI2OK 


C6H4x.       XC6H2(OH)2 
Gallein    I        >C<   | 
Y        XO 

C6H2(OH)2 


COO' 


The  introduction  of  these  colouring  matters  had  a  great 
influence  on  the  manufacture  of  phthalic  acid.  This  acid,  it  will 
be  remembered,  was  proposed  a  good  many  years  since  as  a  source 
for  the  production  of  benzoic  acid,  which  was  largely  in  demand 
for  the  manufacture  of  aniline  blues,  phthalic  acid  when  carefully 
treated  with  lime  yielding  calcium  benzoate.  But  as  phthalic  acid 
was  required  to  be  produced  in  an  extensive  way,  new  experi- 


COLOURING   MATTERS   FROM    COAL-TAR      97 

ments  had  to  be  made  on  the  subject.  The  difficulties  connected 
with  this  were  surmounted  by  the  Badische  Anilin-  und  Soda- 
Fabrik,  who  are  now  the  chief  manufacturers  of  this  body  and  its 
anhydride,  which  is  the  substance  required  ;  when  freshly  pre- 
pared it  is  one  of  the  most  beautiful  products  one  can  see. 

Phthalic  anhydride  and  dichlorophthalic  acid  are  now  also 
manufactured  for  the  preparation  of  the  bluish  shades  of  fluor- 
escein  derivatives  already  referred  to.  But  this  is  not  all ;  it  was 
not  only  necessary  to  produce  these  in  quantity,  but  it  was  neces- 
sary also  to  produce  resorcinol.  This  substance  was  originally  pre- 
pared from  certain  resins,  e.g.  galbanum  by  fusing  it  with  potash, 
or  by  distilling  brazilin,  etc. ;  both  technically  impractical  processes. 
It  was  afterwards  produced  by  fusing  various  halogen  derivatives 
of  phenol  and  benzene  sulphonic  acid  with  alkali  ;  these  also  were 
not  practical  processes.  It  was,  however,  eventually  found  that 
it  could  be  produced  by  fusing  metabenzenedisulphonic  acid  with 
potash,  the  original  observation  being  made  by  Gallik  ;  and  by 
this  process  this  product,  which  was  a  rare  compound,  is  now 
manufactured  and  has  become  a  common  one,  being  produced  in 
very  large  quantities. 

INDIGO  SERIES 

Indigo  is  too  well  known  a  substance  for  me  to  make  any 
remarks  in  reference  to  its  history  as  a  colouring  matter,  and 
with  reference  to  the  chemical  side  of  the  question  I  suppose 
few  substances  have  had  more  work  bestowed  upon  them  than 
this  body,  so  that  I  must  confine  my  few  remarks  to  its  artificial 
formation.  There  is  one  point  of  interest,  however,  connected 
with  indigo,  and  that  is  that  it  was  the  original  source  of  aniline, 
this  base  being  discovered  in  the  products  of  its  destructive 
distillation  by  Unverdorben,  in  1826,  as  already  mentioned. 

Notwithstanding  the  large  amount  of  work  which  has  been 
bestowed  upon  this  colouring  matter,  its  constitution  has  only 
been  lately  arrived  at,  and  for  this,  and  the  methods  of  its 
artificial  formation,  we  are  indebted  to  the  beautiful  and  laborious 
researches  of  Baeyer.  The  first  process  for  its  artificial  produc- 
tion was  patented  by  Baeyer  in  March  1880.  The  process 
consists  in  preparing  orthonitropropiolic  acid  and  acting  upon  it 
in  presence  of  an  alkali,  with  a  reducing  agent,  such  as  grape 
sugar,  xanthate  of  sodium,  etc. : 

2[C9H5(N02)02]  +  H4  =  2C02  +  C16H10N202  +  2  H2O. 

7 


98  THE   BRITISH   COAL-TAR   INDUSTRY 

This  process  renders  the  application  of  artificial  indigo  very 
easy  in  calico  printing,  because  the  products  can  be  applied  to  the 
fabric  and  the  reaction  then  completed,  and  thus  the  indigo  is 
formed  and  fixed  in  the  fibre  ;  and  this  process  is  in  use  in  some 
of  the  print-works  of  Mulhouse,  where  there  is  a  continued 
though  small  demand  for  orthonitropropiolic  acid.  Other 
processes  have  been  discovered  by  Baeyer  for  the  formation  of 
indigo  ;  he  has  found  that  it  can  easily  be  formed  from  ortho- 
nitrobenzaldehyde  by  condensation  with  bodies  containing  the 
CH3CO  group,  such  as  acetone. 

Hitherto  this  artificial  formation  of  indigo  has  not  met  with 
much  practical  success.  This  does  not  arise  from  difficulties  in 
its  manufacture,  but  in  its  cost  compared  with  natural  indigo, 
which  is  a  very  cheap  dyestufF. 

So  far  as  it  has  been  manufactured,  however,  the  possibility 
of  this  has  been  entirely  dependent  upon  scientific  research 
disconnected  with  its  study.  To  prepare  nitropropiolic  acid  it  is 
necessary  to  begin  with  cinnamic  acid  as  a  raw  material.  This 
acid,  until  1877,  was  only  obtained  from  certain  balsams,  and 
was  a  very  costly  material.  It  was  then  discovered  that  it  could 
be  produced  with  comparative  ease  by  the  action  of  acetic 
anhydride  and  an  acetate  on  benzaldehyde  (Jour.  Chem.  Soc.,  xxxi. 
428).  Caro  afterwards  found  that  this  process  might  be 
simplified  by  heating  a  mixture  of  benzylidene  dichloride  with 
sodium  acetate,  and  it  is  by  this  process  that  it  is  now  prepared. 

The  constitution  of  indigo  Baeyer  represents  as  follows  : — 


C6H4CO    CO— C6H4 
NH— C=C— NH. 


Several  derivatives  have  been  made  which  are  interesting 
dyes,  such  as  methyl  indigo,  tetrachlor  indigo,  etc. 

Azo  COMPOUNDS 

The  commencement  of  the  history  of  the  azo  colours  in  an 
industrial  sense  has  little  to  do  with  the  theoretical  side  of  the 
question,  the  early  products  being  the  offspring  of  empirical 
observations,  and  in  no  way  connected  with  the  theory  of  the 
diazo  compounds,  a  condition  of  things  very  different  from  that 
now  existing.  Time  will  not  allow  me  to  enter  into  the  beautiful 


COLOURING   MATTERS   FROM    COAL-TAR      99 

work  of   Griess,   much  of  which  will  be  found    in    the    Philo- 
sophical Transactions  for  1864. 

The  first  definite  compound  of  this  class,  shown  to  possess 
dyeing  powers,  was  a  substance  discovered  by  Prof.  Church  and 
myself,  known  first  as  nitrosonaphthalene,  then  as  azodinaphthyl- 
diamine,  but  now  called  amidoazonaphthalene.  This  substance, 
however,  was  of  no  practical  value,  because  its  salts,  which  are 
violet,  cannot  exist  except  in  the  presence  of  a  certain  amount  of 
free  acid.  This  substance  has  since  been  found  of  value  in  the 
preparation  of  the  Magdala  red. 

The  first  substance  of  this  class  sent  into  the  market  was  the 
phenylic  analogue  of  amidoazonaphthalene  —  viz.  amidoazo- 
benzene,  which  was  discovered  by  Mene.  It  was  introduced  by 
Nicholson,  who  prepared  it  by  a  process  which  has  not  been 
published.  It  was  afterwards  patented  by  Dale  and  Caro  in  1 863. 
It  is  a  yellow  dye,  but  did  not  command  success,  because  of  its 
volatility.  It  has,  however,  since  become  useful  for  the  manu- 
facture of  induline. 

The  first  really  successful  azo  colour  was  Manchester  or 
Bismarck  brown  (triamidoazobenzene),  which  is  produced  by  the 
action  of  nitrous  acid  on  metadiamidobenzene. 

The  next  important  step  took  place  in  1876,  by  the  discovery 
of  chrysoidine,  by  Caro  and  Witt.  Independently,  this  product  is 
prepared  by  the  action  of  diazobenzene  on  metadiamidobenzene. 
About  this  time  the  subject  began  to  be  worked  out  on  a 
scientific  basis,  and  since  then  the  number  of  diazo  dyes  produced 
is  marvellous,  and  it  will  be  useless  for  me  to  do  more  than 
refer  to  one  or  two  of  the  most  important.  About,  this  period 
also  the  value  of  the  sulpho  group  began  to  be  realised,  and  this 
has  greatly  added  to  the  value  of  these  dyes. 

The  first  use  of  the  sulpho  group  in  relation  to  azo  colours 
was  in  connection  with  amidoazonaphthalene,  patented  by  myself 
in  1863. 

During  the  early  history  of  the  coal-tar  colours,  innumerable 
experiments  were  made  with  naphthalene  derivatives  to  produce 
colouring  matters,  but  no  results  of  any  value  were  obtained  ; 
the  experiments  were  mostly  made  with  naphthylamine.  The 
first  colouring  matter  that  was  obtained  from  it  that  was  of  value 
was  Martius's  yellow,  a  dinitronaphthol.  After  this  came  the 
Magdala  red,  which  was  not  much  used.  The  principal  develop- 
ment of  the  coal-tar  colours  of  late  years  has,  however,  been  in 


ioo         THE   BRITISH   COAL-TAR   INDUSTRY 

connection  with  diazo  reaction.  In  these  reactions  /3-naphthol  is 
much  used,  and  this  product,  which  a  few  years  ago  was  unknown, 
is  now  manufactured  by  tons  by  fusing  naphthalene  sulphonic 
acid  with  alkali,  and  is  produced  at  a  few  pence  per  pound. 
Most  of  the  azo  colours  produced  from  benzene  derivatives  are 
of  a  yellow  or  brown  colour,  but,  by  taking  products  of  a  higher 
molecular  weight,  colours  of  different  shades  of  red  are  produced. 
The  one  which  has  commanded  the  greatest  success  is  the  scarlet, 
first  known  as  Meister's  scarlet,  produced  by  the  action  of 
diazoxylene  chloride  on  the  disulphonic  acid  of  /3-naphthol  ;  its 
constitution  may  be  represented  thus  : 

C6H3(CH3)2  -  N  =  N  -  C10H4(OH)(HS03)2. 

In  the  formation  of  bluer  shades,  diazocumene  chloride  is  used. 
The  cumidine  used  is  now  made  from  xylidene,  by  the  beautiful 
reaction  of  Hofmann's,  in  which  an  alcohol  radical  associated  with 
the  nitrogen  leaves  that  element,  and  enters  into  the  hydrocarbon 
radical.  These  scarlets  have  had  a  very  injurious  influence  on 
the  cochineal  market,  and  have  in  many  cases  displaced  cochineal. 
If  a-diazonaphthalene  chloride  be  used  instead  of  the  xylene 
or  cumene  compounds,  the  colours  known  as  Bordeaux  are 
produced.  Then,  again,  where  derivatives  of  a-naphthol  are 
used,  different  results  are  also  obtained,  so  that  great  varieties  of 
products  can  be  produced.  The  preparation  of  these  azo  colours 
is  a  matter  of  great  simplicity,  the  colouring  matter  being 
precipitated  by  bringing  the  products  together,  and,  moreover, 
they  can  be  produced  in  almost  theoretical  yields  ;  hence  they 
are  remarkably  cheap  dyeing  agents.  The  following  are  the 
formulae  of  some  of  these  azo  dyes  : — 

Bismarck  Brown.     NH2C6H4 .  N2 .  C6H3(NH2)2HC1. 
Chrysoidine.     C6H5 .  N2 .  C6H3(NH2)2HC1. 
Fast  Yellow.     KSO3 .  C6H4 .  N2 .  C6H4NH2. 
Manchester  Yellow.     NaSO3 .  C6H4 .  N2 .  C6H4NHC6H5. 

Orange.     NaSO3 .  C6H4 .  N2 .  C10H6(OH). 

£ 

Fast  Red.     NaSO3 .  C10H6 .  N2 .  C10H6(OH). 

Ponceau  G.     C6H5 .  N2 .  C10H4OH(NaSO3)2. 

Ponceau  2R.     (CH3)2C6H5 .  N2 .  C10H4OH(NaSO3)2. 

Bordeau.     C10H7  .-°N2 .  C10H4OH(NaSO3)2. 


COLOURING   MATTERS   FROM    COAL-TAR     101 

From  which  it  will  be  seen  that  the  colour  changes  from  yellow 
to  red  and  claret  by  the  increase  of  the  molecular  weight  of  the 
radicals  introduced,  and  also  by  the  relative  position  occupied  by 
the  groups,  etc. 

QUINOLINE  COMPOUNDS 

Products  of  the  quinoline  series  have  of  late  been  claiming 
attention  in  relation  to  colouring  matters.  It  will  perhaps  be 
remembered  that,  in  the  early  days  of  the  coal-tar  colour  industry, 
a  beautiful  blue  colour  belonging  to  this  series,  discovered  by 
Greville  Williams  (Chem.  News,  nth  Oct.  1860,  219),  was  intro- 
duced. This  substance  was  called  cyanine.  Its  employment  as 
a  dye  for  silk  at  first  produced  quite  a  sensation,  on  account  of 
the  beauty  of  the  colour  ;  but  unfortunately  it  was  too  fugitive 
to  be  of  any  practical  value.  Recent  researches  have  shown  that 
chrysaniline  is  also  to  be  regarded  as  a  body  of  the  quinoline 
class.  Alizarin  blue,  and  the  beautiful  yellow  dye  obtained  from 
acetanilide  by  Fischer,  and  known  as  flavaniline,  are  found  also 
to  belong  to  this  class  of  substances. 

Other  colouring  matters  which  have  since  been  prepared 
from  quinoline  direct  might  be  referred  to  did  time  permit. 
The  peculiar  green  which  is  produced  by  the  condensation  of 
tetramethyldiphenylketone  with  quinoline  is  of  interest,  because 
the  introduction  of  this  quinoline  has  a  very  different  influence 
on  the  resulting  colouring  matter  from  that  of  groups  containing 
amidogen — in  fact,  it  appears  to  act  more  like  phenyl,  as  the 
green  is  very  analogous  to  benzaldehyde  green. 

There  is  a  very  interesting  new  manufacture  growing  out  of 
the  coal-tar  colour  industry,  and  that  is  the  preparation  of 
derivatives  of  quinoline  as  substitutes  for  quinine.  I  have 
mentioned  that  much  work  has  of  late  been  directed  to  the  study 
of  quinine  itself,  and  although  the  artificial  formation  of  this 
substance  has  not  yet  been  discovered,  new  bodies  have  been 
obtained  during  these  investigations  which  are  thought  to  possess 
valuable  medicinal  properties.  This  is  rather  a  remarkable 
development  from  this  industry,  seeing  that  it  is  owing  to 
experiments  made  on  the  artificial  formation  of  quinine  that  it 
owes  its  foundation. 

There  is  another  peculiar  colouring  matter  I  have  not  yet 
referred  to — peculiar,  as  it  contains  sulphur.  I  refer  to 
methylene  blue,  a  very  valuable  dye,  the  constitution  of  which 


102         THE   BRITISH   COAL-TAR   INDUSTRY 

has  been  so  well  worked  out  by  Bernthsen.     I  feel  I  must  be 
content  with  this  slight  reference  to  it. 

As  1  have  shown,  the  coal-tar  colour  industry  originated  in 
this  country,  where  for  some  time  it  was  solely  carried  on.  The 
second  impulse  was  from  France  in  the  discovery  of  magenta  and 
its  blue  and  purple  phenyl  derivatives,  which  were  soon  brought 
to  a  state  of  great  purity  in  this  country.  The  Hofmann  violets 
were  then  discovered  and  produced  also  in  this  country,  several 
other  colours  being  perfected  and  largely  used.  By  this  time 
the  manufacture  of  coal-tar  colouring  matter  had  made  some 
progress  in  Germany  and  Switzerland  ;  crude  products  in  a  cheap 
form  were  first  made,  but  improvements  soon  followed.  The 
subject  of  these  colouring  matters  was  taken  up  with  great 
earnestness  in  the  German  laboratories,  so  much  so  that  it  was 
stated  at  one  time  that  this  industry  was  acting  injuriously  to 
science,  as  it  had  diverted  an  undue  amount  of  attention  from 
other  subjects.  Time  has,  however,  proved  the  groundlessness 
of  this  statement.  This  laboratory  work,  as  well  as  research 
work  generally,  fitted  a  number  of  highly  trained  chemists  to 
enter  the  colour  works,  where  they  soon  improved  the  processes, 
and  thus  they  were  able  to  produce  products  of  a  quality  to 
compete  with  those  of  English  manufacture,  which  had,  owing 
to  their  purity,  given  superior  and  more  reliable  shades  of  colour 
in  the  hands  of  the  dyer  ;  and  the  result  of  the  application  of 
such  scientific  labour  to  this  industry  is  that  Germany  produces 
products  of  the  highest  class  and  at  the  lowest  price.  The  fact 
that  Germany  is  now  the  headquarters  of  this  industry,  raises 
the  important  question,  Why  has  England  allowed  this  state  of 
things  to  come  about  ?  All  the  raw  materials  are  produced  in 
this  country,  both  the  products  from  coal  and  the  other  chemicals 
required,  and,  as  we  have  seen,  the  industry  originated  and  was 
first  carried  on  here,  and,  in  addition,  we  are  the  greatest  con- 
sumers of  the  colouring  matters.  This  fact  is  well  worth 
considering,  and  it  is  many-sided.  In  my  opinion,  the  patent 
laws,  and  the  difficulty  of  preventing  infringements  from  abroad, 
was  one  cause  which  may  have  prevented  this  country  from 
maintaining  its  first  position. 

When  speaking  of  the  early  history  of  the  first  coal-tar  colour 
mauveine,  I  referred  to  this  class  of  infringement  and  how  it  was 
first  met  by  the  proceedings  taken  against  the  agents  employed 
in  this  country,  and  that  this  course  was  so  far  successful,  but 


COLOURING   MATTERS   FROM    COAL-TAR     103 

only  pointed  out  how  easily  the  law  could  be  evaded  if  foreign 
manufacturers  gave  up  responsible  agents  and  sold  direct  to  the 
consumers.  There  being  no  duties  on  such  articles,  no  assistance 
could  be  obtained  at  the  Customs,  and  the  colouring  matters  were 
generally  declared  under  the  name  of  vegetable  dyes  or  extracts, 
so  that  it  was  impossible  to  stop  them  entering  the  country,  and 
even  when  found,  owing  to  the  onus  of  proof  of  their  being 
manufactured  by  the  patentee's  process  resting  with  the  patentee, 
an  almost  insurmountable  difficulty  was  raised,  as  in  most  cases  no 
traces  of  the  products  used  in  the  preparation  were  left  in  the 
colouring  matter.  The  only  other  proceedings  which  could  be 
instituted  were  against  the  consumer  ;  here  again  the  difficulties 
were  practically  insuperable. 

In  most  cases  the  consumers  were  using  the  patentee's 
products  to  some  extent,  and  it  was  impossible  to  know  to  what 
extent ;  in  fact,  without  going  into  the  many  details  connected 
with  this  point,  it  may  be  assumed  that  in  most  cases  proceeding 
against  a  consumer  of  this  kind  of  article  is  practically  useless. 

The  result  of  this  infringement,  by  importation  from  abroad, 
is  that  a  patentee  had  to  compete  against  all  other  manufacturers 
with  the  exception  of  his  own  countrymen. 

There  can  be  but  little  doubt  that  this  state  of  things  has 
had  much  to  do  with  preventing  the  development  of  this 
industry,  and  crippling  enterprise  in  this  country,  as  it  prevented 
manufacturers  even  from  working  under  royalties,  there  being  no 
security  whatever  except  in  name.  Again,  the  fact  that  a 
foreigner  could  take  a  patent  in  this  country,  manufacture  in  his 
own  country,  and  send  the  product  here,  was  a  great  source  of 
loss  and  mischief  to  our  trade.  The  new  patent  laws  may 
probably  alter  this,  but  still  the  difficulty  of  importation  in 
defiance  of  patent  rights  still  remains. 

There  is  another  matter  which  tells  much  against  this  country 
— namely,  that  we  are  not  able  to  export  colour  to  foreign 
countries  upon  the  same  conditions  as  foreign  manufacturers  can 
into  this,  because  we  are  met  with  import  duties  which  handicap 
us  to  a  prohibitive  extent,  whereas  the  foreign  manufacturer, 
being  protected  in  his  own  country,  may  maintain  his  prices 
there  and  sell  at  a  lower  price  in  this  country  ;  but  what  is  still 
more  injurious,  he  may  dispose  of  surplus  production  in  this 
country  at  or  even  below  cost  price.  The  injurious  effect  of  such 
a  course  upon  our  market  can  be  easily  understood  by  business 


io4         THE   BRITISH   COAL-TAR   INDUSTRY 

men,  and  I  need  not  go  into  it  here.  These  are  matters  our 
manufacturers  have  to  contend  with,  and  cannot  help  themselves  ; 
there  is,  however,  one  matter  in  which  they  are  undoubtedly 
at  fault. 

We  find  that  in  Germany  the  manufacturer  understands  the 
value  of  well-trained  chemists,  and  sympathises  with  them  ;  they 
also  realise  the  value  of  theoretical  chemistry — this  is  a  condition 
of  things  we  don't  find  in  this  country. 

Unless  I  am  mistaken,  the  coal-tar  colour  industry  has  acted 
as  the  great  stimulus  to  the  development  of  general  chemical 
industries  of  Germany,  and  these,  by  starting  with  so  much 
scientific  aid  as  they  have  called  to  their  assistance,  have  made  an 
amount  of  progress  during  the  last  twenty-five  years  which  is  most 
remarkable.  Up  to  that  time  England  had  been  the  seat  of  most 
of  the  large  chemical  industries,  and  the  success  which  we  have 
had  appears  to  me  to  have  produced  a  feeling  of  false  security, 
and  more  attention  has  been  paid  by  the  heads  of  firms  to  the 
markets  than  to  the  chemistry  of  their  manufactures. 

1  believe  that  thirty  years  ago  there  were  very  few  chemists 
employed  in  chemical  works,  either  in  this  country  or  on  the 
Continent.  Now  there  are  very  few  without  them  ;  but  in  this 
country  they  are  far  less  numerous  and  much  less  efficient  than 
in  Germany,  and  for  this  our  manufacturers  are  to  a  great  extent 
responsible.  1  am  told  that  at  some  of  our  large  chemical  centres, 
the  chemists,  or  so-called  chemists,  are  sometimes  paid  not  more 
than  could  be  earned  by  a  bricklayer.  If  such  openings  are  put 
by  manufacturers  before  young  men,  their  parents  are  not  likely 
to  give  them  an  expensive  scientific  training.  If  they  get  any, 
they  are  not  likely  to  continue  it  longer  than  enough  to  do 
analysis  very  imperfectly,  say  by  studying  for  about  nine  months. 
An  ordinary  tradesman  would  not  be  considered  efficient  unless 
he  passed  a  much  larger  apprenticeship  than  this,  but  I  know 
teachers  complain  that  it  is  difficult  to  get  students  who  are  to 
be  works  chemists  to  stay  longer  than  this.  The  result  is  that 
when  really  efficient  men  are  wanted,  they  are  not  to  be  found,  and 
they  have  to  be  got  from  abroad.  In  my  address  to  the  Chemical 
Society  last  year,  I  referred  to  the  past  neglect  of  research  at  our 
chemical  schools,  so  that  I  need  not  speak  further  on  that  aspect 
of  the  subject  here,  though  it  is  an  important  one  in  relation  to 
our  industries. 

There  is  no  chasm,  as  we  have  already  seen,  between  pure 


COLOURING   MATTERS   FROM   COAL-TAR     105 

and  applied  chemistry,  they  do  not  even  stand  side  by  side,  but 
are  linked  together,  so  that  a  technical  chemist  needs  to  be  a 
thorough  chemist,  and  unless  we  employ  such  men  we  must  be 
at  a  great  disadvantage  in  relation  to  foreign  manufacturers. 

I  have  now  given  a  very  brief,  and  therefore  a  very  imperfect, 
outline  of  the  history  of  the  coal-tar  colour  industry,  an  industry 
to  which  none  other  can  be  compared  for  its  rapid  progress.  I 
have  drawn  your  attention  to  the  fact  that  it  is  the  offspring  of 
scientific  research,  that  in  return,  as  I  before  stated,  it  has  in 
many  cases  given  a  fresh  impulse  to  research  by  giving  the 
chemist  new  products,  and  also  by  opening  up  new  subjects  of 
theoretical  interest  for  consideration,  and  from  the  fruits  thus 
resulting  again  reaping  further  benefit.  This  linking  together 
of  industrial  and  theoretical  chemistry  has  undoubtedly  been  the 
great  cause  of  its  wonderful  development.  We  now  have  not 
only  all  the  colours  of  the  rainbow,  but  we  have  also  the  more 
sombre,  but  often  not  less  useful,  colours,  and,  moreover,  there 
are  also  great  varieties  of  products  of  similar  colour  possessing 
different  properties  which  fit  them  for  special  uses.  This  industry 
is  also  one  of  no  mean  dimensions.  I  have  not  been  able  to  get 
any  very  recent  statistical  information  on  this  subject,  but  not- 
withstanding the  great  reduction  of  prices  of  the  products  of  late 
years,  yet,  owing  to  the  extended  development  it  has  undergone, 
the  value  of  the  annual  output  has  probably  increased  and  not 
declined,  and  from  what  information  I  have  on  the  subject  I 
should  say  it  is  perhaps  not  less  than  ^3,500,000. 

In  my  remarks  I  have  also  been  led  to  refer  to  some  of  the 
points  connected  with  the  migration  of  this  industry  from  this 
country  to  Germany,  and  the  probable  influence  our  patent  laws 
had  upon  this,  to  the  matter  of  technical  education,  and  the  em- 
ployment of  high-class  chemists  in  chemical  works.  This  latter 
subject  is  undoubtedly  of  great  importance,  and  requires  the 
earnest  consideration  of  our  manufacturers.  If  it  is  found 
profitable  to  employ  chemists  of  this  class  on  the  Continent, 
surely  it  should  be  found  equally  profitable  to  employ  them  here. 
In  conclusion,  I  am  happy  to  say  there  are  signs  of  the  coal-tar 
colour  industry  returning  to  our  country,  in  part  at  any  rate, 
especially  in  relation  to  alizarin,  for  which  there  are  now  three 
large  works  in  existence,  and  the  production  of  other  colouring 
matters  is  also  increasing. 


VII. :    i886 

RECENT    PROGRESS    IN   THE 
COAL-TAR    INDUSTRY 

BY  PROFESSOR  SIR  H.  E.  ROSCOE,  M.P.,  LL.D.,  F.R.S. 
(Discourse  delivered  at  the  Royal  Institution,  i6th  April  1886) 

THOSE  who  have  read  Goethe's  episodes  from  his  life,  known  as 
Dichtung  und  Wahrheit^  will  remember  his  description  of  his 
visit  in  1741  to  the  burning  hill  near  Dutweiler,  a  village  in 
the  Palatinate.  Here  he  met  old  Stauf,  a  coal  philosopher, 
philosophus  per  ignem^  whose  peculiar  appearance  and  more  peculiar 
mode  of  life,  Goethe  remarks  upon.  He  was  engaged  in  an  un- 
savoury process  of  collecting  the  oils,  resin,  and  tar,  obtained  in 
the  destructive  distillation  of  coal  carried  on  in  a  rude  form  of 
coke  oven.  Nor  were  his  labours  crowned  with  pecuniary 
success,  for  he  complained  that  he  wished  to  turn  the  oil  and 
resin  into  account,  and  save  the  soot,  on  which  Goethe  adds  that 
in  attempting  to  do  too  much,  the  enterprise  altogether  failed. 
We  can  scarcely  imagine,  however,  what  Goethe's  feelings  would 
have  been  could  he  have  foreseen  the  beautiful  and  useful 
products  which  the  development  of  the  science  of  a  century  and 
a  half  has  been  able  to  extract  from  Stauf's  evil-smelling  oils. 
With  what  wonder  would  he  have  regarded  the  synthetic  power 
of  modern  chemistry,  if  he  could  have  learnt  that  not  only  the 
brightest,  the  most  varied  colours  of  every  tone  and  shade  can  be 
obtained  from  this  coal  tar,  but  that  some  of  the  finest  perfumes 
can,  by  the  skill  of  the  chemist,  be  extracted  from  it.  Nay,  that 
from  these  apparently  useless  oils,  medicines  which  vie  in  potency 
with  the  rare  vegeto-alkaloids  can  be  obtained,  and  lastly,  perhaps 
most  remarkable  of  all,  that  the  same  raw  material  may  be  made 
to  yield  an  innocuous  principle,  termed  saccharine,  possessed  of 

106 


RECENT  PROGRESS  IN  COAL-TAR  INDUSTRY     107 

far  greater  sweetness  than  sugar  itself.  The  attainment  of  such 
results  might  well  be  regarded  as  savouring  of  the  chimerical 
dreams  of  the  alchemist,  rather  than  expressions  of  sober  truth, 
and  the  modern  chemist  may  ask  a  riddle  more  paradoxical  than 
that  of  Samson,  "  Out  of  the  burning  came  forth  coolness,  and 
out  of  the  strong  came  forth  sweetness  "  ;  and  by  no  one  could 
the  answer  be  given  who  had  not  ploughed  with  the  heifer  of 
science,  "  What  smells  stronger  than  tar  and  what  tastes  sweeter 
than  saccharine  ? "  That  these  are  matters  of  fact  we  may  assure 
ourselves  by  the  most  convincing  of  all  proofs — their  money 
value, — and  we  learn  that  the  annual  value  of  the  products  now 
extracted  from  an  unsightly  and  apparently  worthless  material, 
amounts  to  several  millions  sterling,  whilst  the  industries  based 
upon  these  results  give  employment  to  thousands  of  men. 

SOURCES  OF  THE  COAL-TAR  PRODUCTS 

In  order  to  obtain  these  products,  whether  colours,  perfumes, 
antipyretic  medicines,  or  sweet  principle,  a  certain  class  of  raw 
material  is  needed,  for  it  is  as  impossible  to  get  nutriment  from  a 
stone  as  to  procure  these  products  from  wrong  sources.  All 
organic  compounds  can  be  traced  back  to  certain  hydrocarbons, 
which  may  be  said  to  form  the  skeletons  of  the  compounds,  and 
these  hydrocarbons  are  divisible  into  two  great  classes  :  (i)  the 
paraffinoid,  and  (2)  the  benzenoid  hydrocarbons.  The  chemical 
differences  both  in  properties  and  constitution  between  these  two 
series  are  well  marked.  One  is  the  foundation  of  the  fats,  whilst 
the  other  class  gives  rise  to  the  essences  or  aromatic  bodies. 
Now  all  the  colours,  finer  perfumes,  and  antipyretic  medicines 
referred  to,  are  members  of  the  latter  of  these  two  classes. 
Hence  if  we  wish  to  construct  these  complicated  structures,  we 
must  employ  building  materials  which  are  capable  of  being 
cemented  into  a  coherent  edifice,  and  therefore  we  must  start 
with  hydrocarbons  belonging  to  the  benzenoid  series,  as  any 
attempt  to  build  up  the  colours  directly  from  paraffin  compounds 
would  prove  impracticable.  Of  all  the  sources  of  hydrocarbons, 
by  far  the  largest  is  the  natural  petroleum  oils.  But  these  consist 
almost  entirely  of  paraffins,  and  hence  this  source  is  commercially 
inapplicable  for  the  production  of  colours.  We  have,  however, 
in  coal  itself,  a  raw  material  which  by  suitable  treatment  may  be 
made  to  yield  oils  of  a  valuable  character.  Of  these  treatments, 


io8         THE   BRITISH   COAL-TAR   INDUSTRY 

that  followed  out  in  the  process  of  gas-making  is  the  most 
important,  for  in  addition  to  illuminating  gas  in  abundant  supply, 
tar  is  produced  which  contains  principally  that  benzenoid  class  of 
substances  already  referred  to,  and  which,  to  use  the  words  of 
Hofmann,  "is  one  of  the  most  wonderful  productions  in  the 
whole  range  of  chemistry."  The  production  of  these  latter  as 
distinguished  from  the  paraffinoid  group  appears  to  depend  upon 
a  high  temperature  being  employed,  to  effect  the  necessary 
decomposition. 

The  quantity  of  coal  made  into  coke  for  use  in  the  blast 
furnace  is  larger  than  that  distilled  for  gas-making,  no  less  than 
between  eleven  and  twelve  million  tons  of  coal  being  annually 
consumed  in  the  blast  furnaces  of  this  country  in  the  form  of 
coke,  and  being  capable  of  yielding  two  million  tons  of  volatile 
products.  Up  to  recent  times,  however,  the  whole  of  these 
volatile  products  has  been  burnt  and  lost  in  the  coke  ovens. 
But  lately,  various  processes  have  been  devised  for  preventing 
this  loss,  and  for  obtaining  the  oils,  which  might  be  made  avail- 
able as  colour-producing  materials.  It  is,  moreover,  a  somewhat 
remarkable  fact  that  only  in  one  or  two  cases  have  the  conditions 
been  complied  with  which  render  it  possible  to  obtain  the  neces- 
sary benzenoid  substances.  In  the  ordinary  coking  ovens,  as 
well  as  in  the  blast  furnaces,  although  the  temperature  ultimately 
reached  is  far  in  excess  of  that  needed  to  form  the  colour-giving 
hydrocarbons,  yet  the  heating  process  is  carried  on  so  gradually 
that  the  volatile  products  from  the  coal  are  obtained  in  the  form 
of  paraffinoid  bodies  mainly,  and  hence  are  useless  for  colour- 
making  purposes.  Amongst  the  few  coking  processes  in  which 
the  heat  is  suddenly  applied,  and  consequently  a  yield  of  colour- 
giving  hydrocarbons  is  obtained,  may  be  mentioned  the  patented 
process  of  Simon-Carves,  the  use  of  which  is  now  spreading  in 
England  and  abroad.  The  tar  obtained  in  this  process  is  almost 
identical  in  composition  with  the  average  gas-works  tar,  whilst 
the  coke  also  appears  to  be  equal  for  iron-smelting  purposes  to 
that  derived  from  other  coke-ovens.  A  third  source  of  these 
oils  yet  remains  to  be  mentioned,  viz.  those  obtained  as  a  by- 
product in  blast  furnaces  fed  with  coal. 

Another  condition  has,  in  addition,  to  be  considered  in  this 
industry,  and  that  is  the  nature  of  the  coal  employed  for  distilla- 
tion. It  is  a  well-known  fact  that  if  Lancashire  cannel  be  ex- 
clusively employed  in  gas-making  a  highly  luminous  gas  is 


RECENT  PROGRESS  IN  COAL-TAR  INDUSTRY     109 

obtained,  but  the  tar  is  too  rich  in  paraffins  to  be  a  source  of 
profit  to  the  tar-distiller,  whilst,  on  the  other  hand,  coal  of  a 
more  anthracitic  character,  like  that  from  Newcastle  or  Stafford- 
shire, yields  a  tar  too  rich  in  one  constituent,  viz.  naphthalene, 
and  too  poor  in  another,  viz.  benzene.  It  is  also  known  to 
those  engaged  in  carbonising  coal  principally  for  the  sake  of  the 
tar  that  the  coal  from  different  measures,  even  in  the  same  pit, 
yields  tars  of  very  different  constitution.  That  under  these 
varying  conditions  products  of  varying  composition  are  obtained 
is  a  result  that  will  surprise  no  one  who  considers  the  compli- 
cated chemical  changes  brought  about  in  the  process  of  the 
destructive  distillation  of  coal. 


HISTORY  OF  BENZENE  AND  ITS  DERIVATIVES 

Having  thus  sketched  the  principles  upon  which  the 
formation  of  these  valuable  tar  colours  depends,  we  should  do 
wrong  to  pass  over  the  history  of  the  discovery  of  benzene 
(C6H6),  which  contributed  so  much  to  the  unlocking  of  the 
coal-tar  treasury. 

Faraday  in  1825  discovered  two  new  hydrocarbons  in  the 
oils  obtained  from  portable  gas.  One  of  these  was  found  to  be 
butylene  (C4H8)  ;  to  the  other  Faraday  gave  the  name  of 
bicarburet  of  hydrogen,  as  he  ascertained  its  empirical  formula 
to  be  C2H  (C  =  6).  By  exploding  its  vapour  with  oxygen,  he 
observed  that  one  volume  contains  36  parts  by  weight  of  carbon 
to  3  parts  by  weight  of  hydrogen,  and  its  specific  gravity  com- 
pared with  hydrogen  is  therefore  39-1 

Mitscherlich,  in  1834,  obtained  the  same  hydrocarbon  by 
distillation  of  benzoic  acid,  C7H6O2,  with  slaked  lime,  and 
termed  it  benzin.  He  assumed  that  it  is  formed  from  benzoic 
acid  simply  by  removal  of  carbon  dioxide.  Liebig  denied  this, 
adding  the  following  editorial  note  to  Mitscherlich's  memoir  : — 
"  We  have  changed  the  name  of  the  body  obtained  by  Professor 
Mitscherlich  by  the  dry  distillation  of  benzoic  acid  and  lime, 
and  termed  by  him  benzin,  into  benzol,  because  the  termination 
c  in '  appears  to  denote  an  analogy  between  strychnine,  quinine, 
etc.,  bodies  to  which  it  does  not  bear  the  slightest  resemblance, 
whilst  the  ending  in  c  ol '  corresponds  better  to  its  properties  and 
mode  of  production.  It  would  have  been  perhaps  better  if 

1  Phil.  Trans.,  1825,  p.  440. 


no         THE   BRITISH   COAL-TAR   INDUSTRY 

the  name  which  the  discoverer,  Faraday,  had  given  to  this  body 
had  been  retained,  as  its  relation  to  benzoic  acid  and  benzoyl 
compounds  is  not  any  closer  than  it  is  to  that  of  the  tar  or  coal 
from  which  it  is  obtained." 

Almost  at  the  same  time  Peligot  found  that  the  same  hydro- 
carbon occurs,  together  with  benzone,  C13H10O  (diphenylketone, 
CO(C6H5)2),  in  the  products  of  the  dry  distillation  of  calcium 
benzoate. 

The  different  results  obtained  by  Mitscherlich  and  Peligot 
are  represented  by  the  following  formulae  : — 

C7H6O2  +  CaO  =  C6H6  +  CaCO3. 
(C7H502)2Ca    =C13H10O  +  CaC08. 

Peligot  obtained  benzene  only  as  a  by-product,  exactly  as  in  the 
preparation  of  acetone  (dimethylketone)  from  calcium  acetate  ; 
a  certain  quantity  of  marsh  gas  is  always  formed. 

It  is  not  clear  how  Liebig  became  acquainted  with  the  fact 
that  benzene  is  formed  by  the  dry  distillation  of  coal,  as  his 
pupil  Hofmann,  who  obtained  it  in  1845  from  coal-tar, 
observes  :  "  It  is  frequently  stated  in  memoirs  and  text-books 
that  coal-tar  oil  contains  benzene.  I  am,  however,  unacquainted 
with  any  research  in  which  this  question  has  been  investigated." 
It  is,  however,  worthy  of  remark  that  about  the  year  1834,  at 
the  time  when  Mitscherlich  had  converted  benzene  into  nitro- 
benzene, the  distillation  of  coal-tar  was  carried  out  on  a  large 
scale  in  the  neighbourhood  of  Manchester  ;  the  naphtha  which 
was  obtained  was  employed  for  the  purpose  of  dissolving  the 
residual  pitch,  and  thus  obtaining  black  varnish.  Attempts  were 
made  to  supplant  the  naphtha  obtained  from  wood-tar,  which  at 
that  time  was  much  used  in  the  hat  factories  at  Gorton,  near 
Manchester,  for  the  prepartion  of  "  lacquer,"  by  coal-tar  naphtha. 
The  substitute,  however,  did  not  answer,  as  the  impure  naphtha 
left,  on  evaporation,  so  unpleasant  a  smell  that  the  workmen 
refused  to  employ  it.  It  was  also  known  about  the  year  1838 
that  wood-naphtha  contained  oxygen,  whilst  that  from  coal-tar 
did  not,  and  hence  Mr  John  Dale  attempted  to  convert  the 
latter  into  the  former,  or  into  some  similar  substance.  By  the 
action  of  sulphuric  acid  and  potassium  nitrate,  he  obtained  a 
liquid  possessing  a  smell  resembling  that  of  bitter  almond  oil, 
the  properties  of  which  he  did  not  further  investigate.  This 
was,  however,  done  in  1842  by  Mr  John  Leigh,  who  exhibited 


RECENT  PROGRESS  IN  COAL-TAR  INDUSTRY     in 

considerable  quantities  of  benzene,  nitrobenzene,  and  dinitro- 
benzene,  to  the  Chemical  Section  of  the  British  Association 
meeting  that  year  in  Manchester.  His  communication  is,  how- 
ever, so  printed  in  the  Report  that  it  is  not  possible  from  the 
description  to  identify  the  bodies  in  question. 

Large  quantities  of  benzene  were  prepared  in  1848,  under 
Hofmann's  direction,  by  Mansfield,  who  proved  that  the 
naphtha  in  coal-tar  contains  homologues  of  benzene,  which 
may  be  separated  from  it  by  fractional  distillation.  On  the  i  yth 
of  February  1856,  Mansfield  was  occupied  with  the  distillation 
of  this  hydrocarbon,  which  he  foresaw  would  find  further 
applications,  for  the  Paris  Exhibition,  in  a  still.  The  liquid 
in  the  retort  boiled  over  and  took  fire,  burning  Mansfield  so 
severely  that  he  died  in  a  few  days. 

The  next  step  in  the  production  of  colours  from  benzene  and 
toluene  is  the  manufacture  of  nitrobenzene,  C6H5NO2,  and  nitro- 
toluene,  C7H7NO2.  The  former  compound,  discovered  in  1834 
by  Mitscherlich,  was  first  introduced  as  a  technical  product  by 
Collas  under  the  name  of  artificial  oil  of  bitter  almonds,  and 
Mansfield  in  1847  patented  a  process  for  its  manufacture.  It  is 
now  used  for  perfuming  soap,  but  mainly  for  the  manufacture  of 
aniline  (C6H5NH2)  for  aniline  blue  and  aniline  black  and  for 
magenta.  It  is  made  on  a  very  large  scale  by  allowing  a 
mixture  of  well-cooled  fuming  nitric  acid  and  strong  sulphuric 
acid  to  run  into  benzene  contained  in  cast-iron  vessels  provided 
with  stirrers. 

To  prepare  aniline  from  nitrobenzene,  this  compound  is  acted 
upon  with  a  mixture  of  iron  turnings  and  hydrochloric  acid  in  a 
cast-iron  vessel.  Commercial  aniline  is  a  mixture  of  this  com- 
pound with  toluidine  obtained  from  toluene  contained  in  com- 
mercial benzene.  Some  idea  of  the  magnitude  of  this  industry 
may  be  gained  from  the  fact  that  in  one  aniline  works  near 
Manchester  no  less  than  500  tons  of  this  material  are  manu- 
factured annually.  From  the  year  1857,  after  Perkin's  cele- 
brated discovery1  of  the  aniline  colours,  up  to  the  present  day, 
the  history  of  the  chemistry  of  the  tar  products  has  been  that 

1  See  Lectures  by  Professor  Hofmann,  F.R.S.,  "On  Mauve  and  Magenta," 
nth  April  1862,  and  W.  H.  Perkin,  F.R.S.,  "On  the  Newest  Colouring 
Matters,"  i4th  May  1869,  Proc.  Roy.  Inst.;  also  President's  Address  (Dr 
Perkin,  F.R.S.),  Journal  of  Society  of  Chemical  Industry,  July  1885,  "On 
Coal-Tar  Colours"  (p.  75,  ante). 


ii2         THE   BRITISH   COAL-TAR   INDUSTRY 

of  a  continued   series  of  victories,  each   one    more  remarkable 
than  the  last. 

COAL-TAR  COLOURS 

To  even  enumerate  the  different  chemical  compounds  which 
have  been  prepared  during  the  last  thirty  years  from  coal-tar 
would  be  a  serious  task,  whilst  to  explain  their  constitution  and 
to  exhibit  the  endless  variety  of  their  coloured  derivatives  which 
are  now  manufactured  would  occupy  far  more  time  than  is  placed 
at  my  disposal.  Of  the  industrial  importance  of  these  discoveries, 
the  speaker  reminded  his  audience  of  the  wonderful  potency  of 
chemical  research,  as  shown  by  the  fact  that  the  greasy  material 
which  in  1869  was  burnt  in  the  furnaces  or  sold  as  a  cheap 
waggon  grease  at  the  rate  of  a  few  shillings  a  ton,  received  two 
years  afterwards,  when  pressed  into  cakes,  a  price  of  no  less  than 
one  shilling  per  pound,  and  this  revolution  was  caused  by  Graebe 
and  Liebermann's  synthesis  of  alizarin,  the  colouring  matter  of 
madder,1  which  is  now  manufactured  from  anthracene  at  a  rate  of 
more  than  two  millions  sterling  per  annum  ;  and  it  is  stated  that 
an  offer  was  once  made,  in  the  earlier  stages  of  its  history,  by  a 
manufacturer  of  anthracene  to  the  Paris  authorities  to  take  up  the 
asphalt  used  in  the  streets  for  the  purpose  of  distilling  it,  in  order 
to  recover  the  crude  anthracene. 

Again,  we  have  in  the  azo  scarlets  derived  from  naphthalene 
a  second  remarkable  instance  of  the  replacement  of  a  natural 
colouring  matter,  that  of  the  cochineal  insect,  by  artificial  tar- 
products,  and  the  naphthol  yellows  are  gradually  driving  out  the 
dyes  obtained  from  wood  extracts  and  berries.  It  is,  however, 
true  that  some  of  the  natural  dyestuffs  appear  to  withstand  the 
action  of  light  better  than  their  artificial  substitutes,  and  our 
soldiers'  red  coats  are  still  dyed  with  cochineal. 

The  introduction  of  these  artificial  scarlets  has,  it  is  interesting 
to  note,  greatly  diminished  the  cultivation  of  cochineal  in  the 
Canaries,  where,  in  its  place,  tobacco  and  sugar  are  now  being 
largely  grown. 

Let  us  next  turn  to  inquire  as  to  the  quantities  of  these 
various  products  obtainable  by  the  distillation  of  one  ton  of  coal 

1  "On  the  Artificial  Production  of  Alizarin,  the  Colouring  Matter  of 
Madder,"  by  Professor  H.  E.  Roscoe,  Proc.  Roy.  Inst.,  ist  April  1870  (see 
p.  46,  ante)-,  also  Dr  Perkin,  F.R.S.,  "On  the  History  of  Alizarin,"  Journal 
Society  of  Arts,  3oth  May  1879  (see  p.  54,  ante). 


RECENT  PROGRESS  IN  COAL-TAR  INDUSTRY     113 

in  a  gas-retort.  The  six  most  important  materials  found  in  gas- 
tar  from  which  colours  can  be  prepared,  are  : — 

1.  Benzene.  4.  Metaxylene  (from  solvent  naphtha). 

2.  Toluene.  5.  Naphthalene. 

3.  Phenol.  6.  Anthracene. 

The  average  quantity  of  each  of  these  six  raw  materials  obtainable 
by  the  destructive  distillation  of  one  ton  of  Lancashire  coal  is 
seen  in  Table  I.  Moreover,  this  table  shows  the  average  amount 
of  certain  colours  which  each  of  these  raw  materials  yields,  viz.  : — 

1.  I  .,  z      iu  4-  (Xylidine,  0-07  lb.). 

2.  }  Ma8enta'  °'623  lb-  5.  Vermilline  scarlet,  7-1 1  Ibs. 

3.  Aurin,  1*2  lb.  6.  Alizarin,  2*25  Ibs.  (20  per  cent.). 

Further  it  shows  the  dyeing  power  of  the  above  quantities  of 
each  of  these  colours,  all  obtained  from  one  ton  of  coal,  viz.  : — 

*"  >  Magenta,  500  yards  of  flannel  27  in.  wide. 
3.  Aurin,  120  yards  of  flannel. 
4*  I  Vermilline  scarlet,  2560  yards  of  flannel. 
6.  Alizarin,  255  yards  Turkey-red  cloth. 

Lastly,  to  point  out  still  more  clearly  these  relationships,  the 
dyeing  power  of  one  pound  of  coal  is  seen  in  the  lowest  hori- 
zontal column,  and  a  parti-coloured  flag,  which  exhibits  the  exact 
amount  of  colour  obtainable  from  one  pound  of  Lancashire  coal, 
was  exhibited. 

Let  us  moreover  remember,  in  this  context,  that  no  less  than 
ten  million  tons  of  coal  are  used  for  gas-making  every  year  in 
this  country,  and  then  let  us  form  a  notion  of  the  vast  colouring 
power  which  this  quantity  of  coal  represents. 

The  several  colours  here  chosen  as  examples  are  only  a  few 
amongst  a  very  numerous  list  of  varied  colour  derivatives  of  each 
group.  Thus  we  are  at  present  acquainted  with  about  sixteen 
distinct  yellow  colours  ;  about  twelve  orange  ;  more  than  thirty 
red  colours  ;  about  fifteen  blues,  seven  greens,  and  nine  violets  ; 
also  a  number  of  browns  and  blacks,  not  to  speak  of  mixtures 
of  these  several  chemical  compounds,  giving  rise  to  an  almost 
infinite  number  of  shades  and  tones  of  colour.  These  colours 
are  capable  of  a  rough  arrangement  according  as  they  are  origin- 
ally derived  from  one  or  other  of  the  hydrocarbons  contained  in 
the  coal-tar.  The  fifty  specimens  of  different  colours  exhibited 

8 


114         THE   BRITISH   COAL-TAR   INDUSTRY 


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RECENT  PROGRESS  IN  COAL-TAR  INDUSTRY     115 

may  thus  be  classified,  but  in  this  table,  for  the  sake  of  brevity, 
only  the  commercial  names  and  not  the  chemical  formulae  of 
these  compounds  are  given  (see  Table  II.). 

Azo  COLOURS 

Amongst  the  most  important  of  the  artificial  colouring  matters 
may  be  classed  the  so-called  azo  colours.  These  colours  are 
chiefly  bright  scarlets,  oranges,  reds,  and  yellows,  with  a  few 
blues  and  violets.  They  owe  their  existence  to  the  discovery  by 
Griess,  in  1 860,  of  the  fact  that  the  so-called  azo  group  —  N=N  — 
can  replace  hydrogen  in  phenols  and  amido  compounds.  But  it 
is  to  Dr  O.  N.  Witt  that  is  due  the  honour  of  having  given  the 
first  start  in  a  practical  direction  to  this  class  of  azo  colours  by 
the  discovery  of  chrysoidine,  and  perhaps  still  more  so  by  the 
suggestions  contained  in  a  paper  read  before  the  Chemical  Society. 
Dr  Caro,  of  Mannheim,  was  also  acquainted  with  several  com- 
pounds which  belong  to  this  class  at  the  time  Witt  published  his 
results,  but  it  does  not  appear  that  he  made  practical  use  of  them 
until  Witt  introduced  the  chrysoidines  and  tropeolines.  To 
Roussin,  of  the  firm  of  Poirrier  of  Paris,  is  due  the  credit  of 
having  first  brought  into  the  market  some  of  the  beautiful  azo 
derivatives  of  naphthol.  Griess,  therefore,  as  the  original  dis- 
coverer of  the  typical  compounds  and  reactions  by  which  the  azo 
colours  are  obtained,  may  be  considered  as  the  grandfather, 
whilst  Roussin  and  Witt  are  really  the  fathers,  of  the  azo-colour 
industry.  Nor  must  it  be  forgotten  that  it  is  to  Perkin  we  owe 
the  recognition  of  the  value  of  the  sulpho  group  in  relation  to 
azo  colours,  a  discovery  patented  in  1863.  Moreover  it  is  inter- 
esting to  note  that  changes  in  colour  from  yellow  to  red  and 
claret  are  effected  by  the  increase  in  the  molecular  weights  of  the 
radicals  introduced  as  well  as  by  the  relative  positions  occupied 
by  these  groups. 

INDOPHENOL 

Witt  is  also  the  discoverer  of  a  new  blue  dyestufF  termed 
indophenol,  which  has  been  used  as  a  substitute  for  indigo. 
Certain  difficulties,  however,  have  arisen  in  the  adoption  of  this 
colour  on  the  large  scale.  The  most  important  use  indophenol 
is  at  present  put  to  is  for  producing  dark  blues  on  reds  dyed 
with  azo  colours,  both  on  wool  and  cotton.  The  piece  goods  are 


n6         THE   BRITISH   COAL-TAR   INDUSTRY 


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RECENT  PROGRESS  IN  COAL-TAR  INDUSTRY     117 

dyed  a  uniform  red  first,  and  then  printed  with  indophenol  white  ; 
for  like  indigo  itself  indophenol  yields  a  colourless  body  on 
reduction,  and  this  being  a  very  powerful  reducing  agent  destroys 
the  azo  colour,  being  itself  transformed  into  indophenol  blue. 
The  process  works  with  surprising  nicety  and  is  very  cheap. 
The  blue  is  formed  and  the  red  discharged  with  such  precision 
that  patterns  can  be  produced  in  which  the  blue  discharge  covers 
a  great  deal  more  space  than  the  original  red.  This  new  printing 
process  was  devised  by  Mr  H.  Koechlin,  of  Lorrach.  The  reds 
used  for  the  purpose  are  in  the  case  of  wool  the  usual  azo 
scarlets,  for  cotton  Congo  red. 

ARTIFICIAL  INDIGO 

About  five  years  ago  the  speaker  had  the  honour  of  bringing 
before  this  audience l  the  remarkable  discovery  made  by  Baeyer 
of  the  artificial  production  from  coal-tar  products  of  indigo  blue. 
Since  that  time  but  little  progress  has  been  made  in  this  manu- 
facture, as  the  cost  of  the  process,  unlike  the  case  of  alizarin,  has 
as  yet  proved  too  serious  to  enable  the  artificial  to  compete  success- 
fully in  the  market  with  the  natural  indigo. 

Through  the  kindness  of  a  number  of  eminent  colour  manu- 
facturers in  this  country  and  on  the  Continent,  the  speaker  was 
enabled  to  illustrate  his  subject  by  a  most  complete  series  of 
specimens  both  of  the  colours  themselves  and  of  their  application 
to  the  dyeing  and  printing  of  fabrics  of  all  kinds.  His  thanks 
are  especially  due  to  his  friend  Mr  Ivan  Levinstein,  of  Manchester, 
for  the  interesting  series  of  samples  of  cloth  dyed  with  known 
quantities  of  fifty  different  coal-tar  colours,  each  having  a 
different  chemical  composition  ;  also  to  the  same  gentleman, 
and  to  Messrs  Burt,  Boulton,  &  Hay  wood,  of  London,  for  the 
interesting  and  unique  series  of  specimens  indicating  the  absolute 
quantities  of  products  obtainable  from  one  ton  of  coal,  as  well  as 
for  much  assistance  on  the  part  of  Mr  Levinstein  in  the  prepara- 
tion of  the  experimental  illustrations  for  this  discourse.  To  Dr 
Martius  of  Berlin  for  a  valuable  series  of  colours,  especially  the 
well-known  Congo  red,  made  by  his  firm,  including  samples  of 
wool  dyed  therewith,  he  is  also  much  indebted.  For  the  interest- 

1  "On  Indigo  and  its   Artificial  Production,"  Proc.  Roy.  Inst.,  2;th  May 
1 88 1  (see  p.  71,  ante). 


n8         THE   BRITISH   COAL-TAR   INDUSTRY 

ing  details  concerning  indophenol  and  its  applications  the  speaker 
owes  his  thanks  to  Dr  Witt  and  M.  Koechlin. 


COAL-TAR  ANTIPYRETIC  MEDICINES 

Next  in  importance  to  the  colour  industry  comes  the  still 
more  novel  discovery  of  the  synthetical  production  of  antipyretic 
medicines. 

Up  to  this  time  quinine  has  held  undisputed  sway  as  a 
febrifuge  and  antiperiodic,  but  the  artificial  production  of  this 
substance  has  as  yet  eluded  the  grasp  of  the  chemist.  Three 
coal-tar  products  have,  however,  been  recently  prepared  which 
have  been  found  to  possess  strong  febrifuge  qualities,  which  if 
still  in  some  respects  inferior  to  the  natural  alkaloids,  yet  possess 
most  valuable  qualities,  and  are  now  manufactured  in  Germany 
at  H6chst  and  at  Ludwigshafen  in  large  quantity.  And  here  it 
is  well  to  call  to  mind  that  the  first  tar  colouring-matter  discovered 
by  Perkin  (mauve)  was  obtained  in  1856  during  the  prosecution 
of  a  research  which  had  for  its  object  the  artificial  production  of 
quinine. 

In  considering  the  historical  development  of  this  portion  of 
his  subject,  the  speaker  added  that  it  is  interesting  to  remember 
that  the  initiative  in  the  production  of  artificial  febrifuges  was 
given  by  Prof.  Dewar's  discovery  in  1881  that  quinoline,  the 
basis  of  these  antipyretic  medicines,  is  an  aromatic  compound,  as 
from  it  he  obtained  aniline.  Moreover,  Dewar  and  McKendrick 
were  the  first  to  observe  that  certain  pyridine  salts  act  as  febri- 
fuges. So  that  these  gentlemen  may  be  said  to  be  the  fathers 
of  the  antipyretic  medicines,  as  Witt  and  Roussin  are  of  the 
azo-colour  industry. 

Katrine,  the  first  of  these,  was  discovered  by  Prof.  O. 
Fischer,  of  Munich,  in  the  year  1881,  whilst  engaged  on  his 
investigations  of  the  oxyquinolines.  The  febrifuge  properties  of 
this  substance  were  first  noticed  by  Prof.  Filehne  of  Erlangen. 
Kairine  is  manufactured  from  quinoline,  a  basic  product  derived 
from  aniline  by  heating  it  with  glycerin  and  nitrobenzene  by  the 
following  process.  When  treated  with  sulphuric  acid,  it  forms 
quinoline  sulphonic  acid,  and  this  when  fused  with  caustic  soda 
yields  oxyquinoline,  which  is  then  reduced  by  tin  and  hydro- 
chloric acid  into  tetrahydroxyquinoline,  and  this  again  on  treat- 
ment with  ethyl  bromide  yields  ethyl  tetraoxyquinoline  or  kairine. 


RECENT  PROGRESS  IN  COAL-TAR  INDUSTRY     119 

The  lowering  of  the  temperature  of  the  body  by  this  compound 
is  most  remarkable,  though,  unfortunately,  the  action  is  of  much 
shorter  duration  than  that  effected  by  quinine  itself  ;  but  on  the 
other  hand,  with  the  exception  of  its  burning  taste,  it  exerts  no 
evil  effects  such  as  are  often  observed  after  administration  of  large 
doses  of  quinine.  The  commercial  article  is  the  hydrochloride, 
the  price  is  855.  per  lb.,  and  the  quantity  manufactured  has  lately 
diminished  owing  to  the  discovery  of  the  second  artificial  febrifuge, 
antipyrine. 

The  following  graphical  formula  shows  the  constitution    of 
kairine  :  — 


A 
HC1 

Antipyrine^  the  second  of  these  febrifuges,  was  discovered  in 
1883  by  Dr  L.  Knorr  in  Erlangen,  and  its  physiological  properties 
were  investigated  by  Prof.  Filehne  of  Erlangen.  The  materials 
used  in  the  manufacture  of  antipyrine  are  aniline  and  aceto-acetic 
ether.  The  aniline  is  first  converted  into  phenylhydrazine,  a 
body  discovered  by  Emil  Fischer  in  1876.  This  body  combines 
directly  with  aceto-acetic  ether,  with  separation  of  water  and 
alcohol,  to  form  a  body  called  pyrazol  (C10H10N2O).  The 
methyl  derivative  of  pyrazol  derived  by  treating  it  with  iodide  of 
methyl,  is  antipyrine,  its  composition  being  CUH12N2O.  As  a 
febrifuge,  antipyrine  is  superior  in  many  respects  to  kairine  and 
even  to  quinine  itself.  It  equals  kairine  in  the  certainty  of  its 
action,  whilst  in  its  duration  it  resembles  quinine.  It  is  almost 
tasteless  and  odourless,  is  easily  soluble  in  cold  water,  and  takes 
the  form  of  a  white  crystalline  powder.  Its  use  as  a  medicine  is 
accompanied  by  no  drawbacks.  It  occurs  in  commerce  in  the 
free  state.  The  production  of  antipyrine,  in  spite  of  these 
valuable  qualities,  is  as  yet  small,  its  chief  employment  being  in 
Germany,  where  it  has  been  successfully  used  in  cases  of  typhoid 
epidemic.  The  price  is  6s.  per  lb. 

Thalline,  the  third  of  the  artificial  febrifuges,  is  offered  as 
the  tartrate  and  sulphate.  It  is  manufactured  by  the  Badische 
Company.  Thalline  is  said  to  be  used  as  an  antidote  for  yellow 
fever.  Its  scientific  name  is  tetrahydroparaquinanisol,  and  it  was 
first  prepared  by  Skraup  by  the  action  of  methyl  iodide  and  potash 
on  paroxyquinoline. 


120         THE   BRITISH   COAL-TAR   INDUSTRY 

We  must,  however,  bear  in  mind  that  none  of  these  syntheti- 
cal febrifuges  are  antiperiodics,  and  therefore  cannot  be  employed 
instead  of  the  natural  alkaloid  quinine  in  cases  of  ague  or  inter- 
mittent fevers. 

COAL-TAR  AROMATIC  PERFUMES 

A  third  group  of  no  less  interest  comprises  the  artificial 
aromatic  essences,  and  of  these  may  here  be  mentioned,  in  the 
first  place,  cumariny  C9H6O2,  the  crystalline  solid  found  in  the 
sweet  woodruff,  in  Tonka  bean,  and  in  certain  sweet-scented 
grasses.  This  is  now  artificially  prepared  by  acting  upon  sodium 
salicyl  aldehyde  with  acetic  anhydride  by  the  reaction  which  is 
associated  with  the  name  of  Dr  Perkin,  and  is  used  in  the  manu- 
facture of  the  perfume  known  as  "  extract  of  new-mown  hay." 

A  second  interesting  case  of  a  production  of  a  naturally 
occurring  flavour,  is  the  artificial  production  of  vanillin,  the 
crystalline  principle  of  vanilla.  Vanilla  is  the  stalk  of  the  Vanilla 
planifolia,  which  encloses  in  its  tissues  prisms  of  crystalline  vanillin, 
to  which  substance  it  owes  its  fragrance.  Tiemann  and  Harrmann 
showed  that  vanillin  is  the  aldehyde  of  methyl  protocatechuic  acid. 

C6H3(OH)(OCH8)CHO.     [CHO  :  OCH3  :  OH  =  i  :  3  :  4]. 

The  chief  seats  of  the  vanilla  productions  are  on  the  slopes  of 
the  Cordilleras  north-west  of  Vera  Cruz  in  Mexico,  also  the 
island  of  Reunion,  and  in  the  Mauritius.  Since  the  discovery  of 
the  artificial  production  of  vanillin,  the  growth  of  the  vanilla  has 
been  very  much  restricted. 

A  variety  of  vanilla,  termed  vanillon,  obtained  in  the  East 
Indies,  has  long  been  used  in  perfumery  for  preparing  "  essence 
of  heliotrope."  This  contains  vanillin  together  with  an  oil,  which 
is  probably  oil  of  bitter  almonds.  The  essence  of  white  heliotrope 
is  now  entirely  prepared  by  synthetical  operations.  It  is  manu- 
factured by  adding  a  small  quantity  of  artificial  oil  of  bitter 
almonds  to  a  solution  of  artificial  vanillin  ;  when  these  substances 
are  allowed  to  remain  for  some  time  in  contact,  the  mixture 
assumes  an  odour  closely  resembling  that  of  natural  heliotrope. 


VIII. :    i886 

THE   SCIENTIFIC   DEVELOPMENT   OF  THE 
COAL-TAR   COLOUR   INDUSTRY 

BY  PROFESSOR  R.  MELDOLA,  F.C.S.,  F.I.C. 

(Journal  of  the  Society  of  Arts^  1886,  p.  759) 

IT  will,  I  think,  be  conceded  that  the  manufacture  of  coal-tar 
products  is  par  excellence  the  most  scientific  of  the  chemical  in- 
dustries. This  high  position  may  fairly  be  claimed  for  the 
industry  when  we  consider  the  number  and  complexity  of  the 
products,  the  delicacy  of  many  of  the  reactions  employed,  the 
special  arrangement  of  plant  required,  and  the  intimate  knowledge 
of  the  chemistry  of  the  aromatic  compounds  which  the  colour 
chemist  must  at  the  present  time  possess.  Moreover,  the 
industry  is  of  comparatively  recent  growth — it  has  been  born  and 
has  reached  its  present  development  within  the  last  thirty  years, 
so  that  the  successive  phases  of  its  evolution  can  be  clearly  traced. 
For  these  reasons  the  subject  is  well  calculated  to  throw  light 
upon  the  general  question  of  technical  chemical  education,  a 
question  of  which  the  importance  to  the  country  at  large  now 
bids  fair  to  become  duly  recognised. 

In  the  brief  historical  sketch  which  I  now  propose  to  lay 
before  you,  I  shall  mention  only  those  discoveries  which  may  be 
considered  to  mark  distinct  commercial  epochs  in  the  develop- 
ment of  the  industry.  The  successive  steps  in  this  development 
will  furnish  us  with  one  of  the  most  striking  illustrations  of  the 
utilisation  of  scientific  discovery  for  industrial  purposes,  and  the 
reaction  of  industry  upon  pure  science. 

Commencing  in  the  year  1856,  the  foundation  of  the  coal-tar 
colour  industry  was  laid  by  Perkin,  by  the  discovery  of  mauve, 


121 


122         THE   BRITISH   COAL-TAR   INDUSTRY 

a  violet  dye,  obtained  accidentally  in  the  course  of  an  investiga- 
tion having  for  its  object  the  preparation  of  quinine  by  an  artificial 
synthesis.  In  1860,  magenta,  which  had  formerly  been  made  in 
small  quantities  by  expensive  processes,  was  rendered  a  product 
of  the  first  order  of  commercial  importance,  by  the  discovery  of 
the  arsenic  acid  process  by  Medlock  and  E.  C.  Nicholson  simul- 
taneously. During  this  same  year,  phenylated  blues  were  first 
produced  by  Girard  and  De  Laire,  by  the  action  of  aniline  upon 
a  magenta  base  at  a  high  temperature.  These  blues  had  but  a 
limited  application  owing  to  their  insolubility,  and  their  value 
was  enormously  enhanced  by  Nicholson's  discovery  in  1862,  that 
these  colours  could  be  converted  into  soluble  sulphonic  acids. 
The  first  azo  colour,  amido-azobenzene,  a  basic  yellow  dye,  was 
introduced  in  1863,  by  the  firm  of  Simpson,  Maule  &  Nicholson, 
under  the  name  of  aniline  yellow.  In  this  same  year  the 
methylic  and  ethylic  derivatives  of  magenta  were  manufactured 
by  the  same  firm,  under  the  name  of  Hofmann  violets,  in 
honour  of  their  discoverer.  Azodiphenyl  blue,  the  first  of  the 
colouring  matters  now  known  as  indulines,  and  Manchester 
yellow,  appeared  in  1864;  and  in  1866  Bismarck  brown 
(triamidoazobenzene)  was  first  manufactured  at  Manchester. 
The  same  year  (1866)  was  marked  by  the  introduction  of 
Coupler's  nitrobenzene  process  for  the  manufacture  of  magenta. 
In  1868,  Graebe  and  Liebermann  gave  to  the  world  their  great 
discovery  of  the  chemical  constitution  of  alizarin,  and  in  the 
following  year  the  manufacture  of  this  colouring  matter  from 
anthracene  was  commenced.  The  first  members  of  the  great 
family  of  the  "  phthalemes,"  viz.  gallem  and  fluorescem,  were 
discovered  by  Baeyer  in  1871  ;  and  the  first  technical  application 
of  this  discovery  was  made  in  1874  by  Caro,  who  introduced  the 
beautiful  pink  tetrabromfluorescem  into  commerce,  under  the 
name  of  eosin.  Diamidoazobenzene  was  discovered  by  Caro 
and  Witt  independently  in  1875,  and  was  introduced  into  com- 
merce by  the  latter  as  chryso'fdine.  A  great  impetus  was  given 
to  the  technical  production  of  azo-colouring  matters  by  this  dis- 
covery, the  napthol  oranges  and  other  "  tropoeolines,"  fast-red, 
the  ponceau  scarlets,  etc.,  appearing  in  1878.  Methylene  blue 
and  acid  magenta  were  introduced  by  Caro  in  1877,  and  in  the 
same  year  the  old  and  fugitive  aniline  yellow  was  converted 
into  a  valuable  acid  yellow  by  Grassier,  who  patented  a  process 
for  converting  the  base  into  a  sulphonic  acid.  Malachite  green 


SCIENTIFIC  DEVELOPMENT  OF  THE  INDUSTRY  123 

was  introduced  in  1878,  and  in  1879  the  first  member  of  the  now 
important  group  of  secondary  azo  compounds  appeared  under 
the  name  of  Biebrich  scarlet.  It  is  these  secondary  azo  scarlets, 
and  especially  the  croceine  scarlets  (discovered  in  1 88 1),  which 
are  exterminating  the  cochineal  industry.  The  year  1880  was 
marked  by  the  brilliant  discovery  of  the  constitution  of  indigo, 
and  the  synthesis  of  this  colouring  matter  by  Baeyer,  a  discovery 
which  is  none  the  less  a  triumph  of  synthetical  chemistry  because 
the  manufacture  is  not  at  present  successful  from  a  commercial 
point  of  view.  Indophenols  were  introduced  by  Koechlin  and 
Witt  in  1 88 1,  and  in  1883  appeared  Caro's  first  patent  for  the 
production  of  colouring  matters  of  the  rosaniline  group  by  the 
method  of  "  condensation  "  with  phosgene  gas,  in  the  presence  of 
suitable  condensing  agents. 

This  chronological  record  comprises  nearly  all  the  chief 
colouring  matters  from  coal-tar  which  are  or  have  been  of  in- 
dustrial value.  It  is  important  to  note  that  the  list,  even  as  it 
stands  in  the  form  of  a  bald  statement  of  facts  in  chemical  history, 
reveals  the  existence  of  that  fundamental  law  of  the  "  survival  of 
the  fittest."  Old  products  have  been  displaced  by  newer  ones, 
as  fresh  discoveries  were  made,  or  processes  improved,  and  to 
the  chemist  it  is  of  interest  to  observe  how  this  development  of 
an  industry  has  gone  on  part  passu  with  the  development  of  the 
science  itself.  The  moral  conveyed  to  the  manufacturer  is 
sufficiently  obvious.  If  we  are  to  recover  our  former  supremacy 
in  this  industry,  we  must  begin  by  dispelling  conservative  ideas 
—we  must  realise  the  fact  that  no  existing  process  is  final,  and 
that  no  product  at  present  sent  into  the  market  is  destined  to 
survive  for  an  unlimited  period.  The  scientific  manufacturer 
must  be  brought  to  see  that  present  success  is  no  guarantee  for 
future  stability,  and  unless  he  realises  this  position  in  its  fullest 
significance,  he  may  find  the  sale  of  his  standard  products  gradu- 
ally falling  off,  or  be  compelled  to  wake  up  to  the  unpleasant  fact 
that  his  competitors  are  underselling  him,  owing  to  improved 
methods  of  manufacture. 

It  may  appear  to  many  that  I  am  here  simply  preaching  the 
doctrine  of  progress,  and  that  the  remarks  which  I  have  offered 
are  mere  truisms.  Unfortunately,  the  facts  of  the  case  render 
this  appeal  necessary.  It  must  never  be  forgotten  that  the  coal- 
tar  colour  industry  is  essentially  of  English  origin.  It  was 
Faraday  who  first  discovered  benzene  in  1825  ;  it  was  Mansfield 


i24         THE   BRITISH   COAL-TAR   INDUSTRY 

who,  in  1847,  first  isolated  this  substance  in  large  quantities  from 
coal-tar,  and  showed  how  nitro-benzene  could  be  manufactured 
therefrom.  The  beginning  of  the  colour  industry  was  Perkin's 
discovery  of  mauve  ;  and  the  introduction  of  the  new  colour  into 
dyeing  establishments  was  due  to  the  example  set  by  Messrs 
Pullar,  of  Perth,  in  1856.  The  manufacture  of  magenta  on  a 
large  scale  was  the  result  of  the  discovery  of  the  arsenic  acid 
process  by  Medlock  and  Nicholson  ;  and  the  phenylic  blues 
were  made  commercially  valuable  by  Nicholson.  The  first  azo 
colours,  aniline  yellow  and  Manchester  brown,  as  well  as  Man- 
chester yellow  (dinitro-a-naphthol),  were  manufactured  in  this 
country.  We  may  thus  fairly  lay  claim  to  have  given  to  the 
commercial  world  the  types  of  all  the  more  important  colouring 
matters  of  the  present  time.  If,  as  is  certainly  the  case,  the 
development  of  these  typical  products  has  been  allowed  to  take 
place  in  other  countries,  it  behoves  us,  as  a  practical  nation,  to 
inquire  closely  into  the  cause  of  this  success  abroad,  a  success 
which  will  appear  all  the  more  remarkable  when  we  bear  in  mind 
that  we  are  the  largest  European  producers  of  the  raw  material, 
gas  tar,  out  of  which  the  colours  are  manufactured,  as  well  as 
being  among  the  largest  consumers  of  the  dyes  themselves.  It 
is  estimated  that  the  amount  of  tar  distilled  annually  in  this 
country  is  about  500,000  tons,  and  it  is  certain  that  we  distil 
at  least  one-half  of  the  whole  amount  of  tar  produced  in 
Europe.  The  present  state  of  affairs  is  that  our  competitors 
can  afford  to  import  the  raw  materials  from  us,  to  manufacture 
and  return  the  colours  so  as  to  compete  with  us  successfully  in 
our  own  markets,  and  to  undersell  us  in  the  foreign  markets. 
The  bare  mention  of  these  facts  will  be  sufficient  to  indicate 
the  existence  of  something  requiring  radical  reform  in  our 
manufacturing  system. 

Before  submitting  to  you  the  statistics  of  this  industry  which 
I  have  been  able  to  collect,  I  think  it  is  desirable  to  make  an 
attempt  to  show  the  inner  mechanism  by  which  chemical  science 
has  been  and  is  being  so  successfully  adjusted  to  commercial 
wants  by  our  Continental  neighbours.  I  regret  exceedingly  that 
my  predecessors  on  this  and  other  platforms  have  not  left  me 
the  chance  of  giving  a  general  sketch  of  the  chemical  develop- 
ment of  the  different  groups  of  colouring  matters.  In  fact,  I 
find  myself  suffering  here  from  several  distinct  disadvantages,  but 
I  hope,  with  your  forbearance,  to  make  the  best  of  the  situation. 


SCIENTIFIC  DEVELOPMENT  OF  THE  INDUSTRY  125 

It  will  serve  my  purpose  equally  well,  or  perhaps  even  better,  to 
confine  my  illustration  to  one  particular  group  of  colouring 
matters.  The  more  striking  achievements,  such  as  the  syntheses 
of  alizarin  and  indigo,  are  now  so  familiar  to  chemical  audiences, 
that  their  repetition  would  be  unnecessary.  Equally  instructive, 
from  the  present  point  of  view,  would  be  the  history  of  the 
colouring  matters  of  the  rosaniline  group,  and  I  can  only  express 
a  passing  regret  that  time  will  not  permit  me  to  recapitulate  the 
steps  in  the  beautiful  series  of  investigations  which  led  to  the 
establishment  of  the  structural  formula  of  rosaniline  and  its 
derivatives  by  E.  and  O.  Fischer,  and  then  to  the  synthesis  of 
these  colours  by  Caro  from  ketone  bases.  The  principle  which  I 
wish  to  bring  out  may  seem  a  strange  one  to  a  "  practical " 
people,  but  I  am  convinced  that  the  whole  secret  of  success  abroad 
is  the  spirit  of  complete  indifference  to  immediately  successful 
results  in  which  the  researches  are  carried  on.  I  say,  "  immedi- 
ately successful,"  because  it  would  of  course  be  absurd  on  the 
part  of  an  investigator  not  to  take  advantage  of  any  discovery 
which  happened  to  be  of  commercial  value.  But,  as  a  general 
principle,  the  question  of  practical  utility  does  not  in  the  first 
place  enter  into  the  work.  The  great  development  of  this  and 
many  other  industries  is  mainly  due  to  the  complete  and  thorough 
recognition,  on  the  part  of  our  competitors,  of  the  vital  import- 
ance of  chemical  science.  In  this  country,  where  the  word 
"  practical "  threatens  to  become  a  reproach,  we  put  science  into 
the  background,  and  attach  all  importance  to  the  mere  technique 
of  our  manufactures.  If  I  might  venture  to  offer  an  aphorism 
to  the  English  manufacturer,  it  would  be  to  the  effect  that  he 
should  look  after  the  science,  and  leave  the  technique  to  take  care 
of  itself. 

After  these  considerations,  you  will  see  that  it  is  a  matter 
of  perfect  indifference  whether  I  take  by  way  of  illustration 
products  which  have  been  successful  from  a  financial  point  of 
view  or  not.  In  order  to  give  greater  emphasis  to  the  principle, 
1  propose,  however,  to  consider  the  history  of  some  colouring 
matters  which  have  found  a  market  value,  and  I  select  this  group 
with  the  more  readiness  because,  on  the  one  hand,  it  was  not 
treated  of  last  year  by  Dr  Perkin,  and,  on  the  other  hand,  it 
furnishes  a  splendid  illustration  of  the  way  in  which  these  coal- 
tar  products  are  being  scientifically  developed  in  the  foreign 
laboratories. 


126         THE   BRITISH   COAL-TAR   INDUSTRY 

In  1863,  Mr  E.  C.  Nicholson  discovered  a  basic  orange 
colouring  matter  among  the  by-products  formed  during  the 
manufacture  of  magenta  by  the  arsenic  acid  process.  The 
method  of  isolating  this  substance  in  a  state  of  purity  was  very 
skilfully  worked  out  by  Messrs  Simpson,  Maule  &  Nicholson, 
and  the  colour  was  introduced  into  the  market  under  the  name 
of  phosphine.  This  dye  was  the  first  basic  orange  discovered, 
and  the  advantages  which  it  possessed  for  certain  kinds  of  dyeing 
enabled  the  manufacturers  to  sell  it  at  a  price  which  helped  to 
cheapen  the  cost  price  of  magenta  to  an  appreciable  extent.  The 
chemical  composition  of  the  substance  was  established  in  1863 
by  Hofmann,  who  assigned  the  formula  C2oHi7N3  .  H2O,  and 
described  the  base  under  the  name  of  chrysaniline.  Although 
other  and  cheaper  basic  orange  colouring  matters  have  since  been 
discovered,  chrysaniline  still  finds  a  distinct  use ;  and  I  am 
informed  by  Messrs  Brooke,  Simpson  &  Spiller  that  the 
amount  of  this  colour  now  sold  is  not  appreciably  less  than  at 
the  time  of  its  introduction  by  their  predecessors.  The  chemical 
constitution  of  chrysaniline  remained  unknown  till  about  two 
years  ago,  when  the  problem  was  solved  by  O.  Fischer  (Ber.y 
1884,  p.  203).  In  order  to  be  able  to  follow  the  steps  in  the 
investigation,  it  will  be  necessary,  in  the  first  place,  to  go  back 
to  the  discovery  of  another  colouring  matter,  called  flavaniline, 
of  which  the  existence  was  made  known  by  O.  Fischer  and 
C.  Rudolph  in  1882  (Ber.,  1882,  p.  1500).  Flavaniline  was 
produced  by  the  action  of  dehydrating  agents,  such  as  zinc 
chloride,  upon  acetanilide,  this  fact  having  been  observed  by 
Rudolph  in  i88i,and  the  practical  manufacture  of  the  colour 
having  been  carried  on  under  a  patent  by  Messrs  Meister,  Lucius 
&  Brttning,  of  the  Hoechst  colour  works.1  Supplied  with  a  large 
quantity  of  the  pure  crystalline  material  by  the  manufacturers, 
Messrs  Fischer  and  Rudolph  established  the  formula  of  flavaniline, 
C16H14N2,  and  showed  that  its  formation  from  acetanilide  might 
be  expressed  by  the  equation  : 

2C6H5 .  NH  .  C2H3O  -  2OH2  =  C16H14N2. 

By  the  action  of  nitrous  acid  upon  flavaniline  a  diazo  compound 
was  produced  which,  by  the  usual  method  of  decomposition  by 
water,  gave  a  phenolic  derivative  termed  flavenol,  possessing 

1  I  am  indebted  to  this  firm  for  having  kindly  supplied  me  with  specimens 
of  these  products  for  exhibition. 


SCIENTIFIC  DEVELOPMENT  OF  THE  INDUSTRY  127 

the  formula  C16H12N  .  OH,  thus  proving  that  flavaniline  con- 
tained a  displaceable  NH  group.  By  heating  flavenol  with  zinc 
dust,  a  base  was  obtained  having  the  formula  C16H13N,  and 
termed  flavoline.  This  base  had  an  odour  resembling  that  of 
quinoline,  and  all  its  properties  suggested  to  the  authors  that 
flavaniline  was  in  reality  a  quinoline  derivative.  That  flavaniline 
was  amido-flavoline  was  proved  by  nitrating  the  latter  base,  and 
reducing  the  nitro  compound,  when  flavaniline  was  obtained. 
In  a  later  publication  by  Besthorn  and  Fischer  (Ber.y  1883,  p. 
68)  it  was  announced  that  flavenol,  when  oxidised  by  potassium 
permanganate  in  an  alkaline  solution,  gave  an  acid  which,  on 
distilling  with  lime,  furnished  a  base  having  all  the  characters  of 
lepidine.  By  the  continued  oxidation  of  flavenol  with  excess  of 
alkaline  permanganate,  another  acid  was  obtained,  which  proved 
to  be  picoline-tricarbonic  acid,  and  the  latter,  on  further  oxidation, 
gave  picoline-tetracarbonic  acid  (Eer.^  1884,  p.  2925). 

So  much  for  the  facts  ;  now  for  their  interpretation.  The 
production  of  flavenol  from  flavaniline  by  the  diazo  reaction 
shows  that  the  respective  formulas  of  these  substances  are  : 

C16H12(NH2)N  C16H12(OH)N. 

Flavenol  gave,  as  the  first  product  of  oxidation,  lepidine- 
carbonic  acid,  of  which  the  formula  is  Ci0H8N(CO2H),  and  by 
further  oxidation  it  gave  picoline-tricarbonic  acid,  of  which  the 
formula  is  C6H4N(CO2H)3.  Now  the  C-atoms  oxidised  by  the 
breaking  down  of  the  1 6 -carbon  atom  flavenol  into  n -carbon 
atom  lepidine-carbonic  acid,  are  those  C-atoms  which  in  flavenol 
are  associated  with  the  hydroxyl  group,  because  this  group  is  no 
longer  contained  in  the  product  of  oxidation.  Thus  the  formulas 
of  flavaniline,  flavenol,  and  flavoline  are  better  expressed  as  : 

C10H8N .  C6H4(NH2) 

C10H8N.C6H4(OH) 

C10H8N.C6H5. 

From  this  it  appears  that  flavanaline  is  amidophenyl-lepidine, 
flavenol  hydroxyphenyl-lepidine,  and  that  flavoline  is  phenyl- 
lepidine. 

The  central  nucleus  of  flavaniline  having  thus  been  shown  to 
be  lepidine  (which  is  methylquinoline),  the  next  question  to 
be  settled  was  the  mode  of  formation  of  the  colour  base  from 
acetanilide.  The  authors  suggest  that  at  the  high  temperature 


128         THE   BRITISH   COAL-TAR   INDUSTRY 

of  the  reaction,  acetanilide,  in  the  first  place,  becomes  transformed 
into  the  isometric  orthoamidoacetophenone  : 

CH3 
?Hs  rn/C:0 

^6H4< 

C6H5.NH.C:0  XNH2 

Acetanilide.  Amidoacetophenone. 

By  the  condensation  of  two  molecules  of  the  amidoaceto- 
phenone  with  the  elimination  of  two  molecules  of  water,  flav- 
aniline  would  be  produced  in  a  manner  analogous  to  the 
formation  of  mesitylene  by  the  condensation  of  three  molecules 
of  acetone  under  the  influence  of  dehydrating  agents  : 

CH3  CH3 


/ 
C6H4<(  |  =C6H4<  | 

\N  =  |H2Oi  =  C  -  C6H4  .  NH2  \N  =  C  -  C6H4  .  NH2 

The  accuracy  of  this  suggestion  was  verified  by  showing  that 
orthoamidoacetophenone  is  present  in  small  quantity  when  the 
reaction  is  arrested  as  soon  as  the  formation  of  colouring  matter 
commences  ;  and  conversely,  when  pure  orthoamidoacetophenone 
was  heated  with  zinc  chloride,  flavaniline  was  produced  in  small 
quantity. 

We  may  be  permitted  to  pause  at  this  stage  of  the  investiga- 
tion before  proceeding  to  consider  the  connection  of  this  work 
with  the  constitution  of  chrysaniline.  These  results  cannot  but 
be  regarded  by  chemists  as  a  very  beautiful  piece  of  investigation  ; 
but  the  person  of  a  "  practical  "  turn  of  mind  may  possibly  want 
to  know  what  bearing  they  have  upon  the  question  of  market 
value  —  the  question  which  the  manufacturer  but  too  frequently 
considers  as  the  only  one  of  importance.  Now,  it  is  the  essence 
of  chemical  science  —  as  indeed  of  all  other  sciences  —  that  every 
discovered  fact  is  related  to  other  groups  of  facts,  and,  although 
the  relationship  may  not  at  once  be  apparent,  it  is  only  a  matter 
of  further  development  that  is  necessary  in  order  to  reveal 
relationships  which  are  obscure  on  account  of  our  imperfect 
knowledge.  Thus  the  policy  of  looking  at  a  chemical  product 
from  the  narrow  point  of  view  of  immediate  utility  is  not  only 
unscientific,  but  it  is  detrimental  to  the  interests  of  the  manu- 


SCIENTIFIC  DEVELOPMENT  OF  THE  INDUSTRY  129 

facturer  himself.  Every  new  compound  or  process  discovered — 
every  structural  formula  established  by  legitimate  investigation — 
may  have  an  enormous  influence,  directly  or  indirectly,  upon  the 
market  value  of  products  at  present  sent  into  commerce.  Our 
manufacturers  must  realise  this  if  they  wish  to  recover  their 
position  in  the  coal-tar  industry,  or  in  fact  in  any  other  chemical 
industry.  There  is  no  branch  of  manufacture  so  perfect  as  not 
to  be  open  to  further  improvement,  and  until  the  broad  spirit  of 
scientific  development  is  made  to  replace  the  suicidal  policy  of 
immediate  utility,  our  position  as  a  manufacturing  nation  is  not 
likely  to  be  improved. 

In  order  to  justify  this  digression  by  the  particular  instance 
now  under  consideration,  we  must  return  to  the  work  of  Messrs 
Fischer  and  Besthorn.  The  discovery  that  flavaniline  was  a 
quinoline  derivative  was  of  importance  as  a  principle,  quite  apart 
from  any  immediate  value  attaching  to  the  dyestuff  itself .  Up 
to  the  time  of  this  discovery,  the  quinoline  derivatives  had  been 
practically  of  no  importance  in  the  tinctorial  industries,  but  as  a 
consequence  of  the  present  investigation  the  question  at  once 
suggested  itself  whether  the  analogous  bases  of  high  boiling-point, 
which  are  present  in  coal-tar,  such,  for  example,  as  acridine, 
might  not  be  utilised  as  sources  of  colouring  matters.  I  may 
remind  you  that  the  fact  of  quinoline  being  an  aromatic  compound 
was  first  established  by  the  researches  of  our  Chairman  this 
evening,  Professor  Dewar,  who  obtained  aniline  from  this  base. 
In  a  subsequent  paper  on  chrysaniline  (O.  Fischer  and  G.  KSrner, 
Ber.,  1884,  p.  203),  it  was  pointed  out  that  in  the  course 
of  his  investigations  upon  rosaniline  Fischer  had  observed  that 
the  former  base,  like  rosaniline,  was  capable  of  furnishing  a 
diazo  compound.  An  observation  made  by  Claus  is  also  men- 
tioned, viz.  the  conversion  of  chrysaniline  into  a  phenol  (chryso- 
phenol) by  heating  to  a  high  temperature  with  hydrochloric  acid 
in  accordance  with  the  equation  : 

C16H15N3 .  HC1  +  H20  =  C19H15N20  +  NH4C1 

Chrysaniline  hydrochloride.     Chrysophenol. 

The  investigation  of  flavaniline  appears  to  have  given  an 
impetus  to  the  ideas  respecting  chrysaniline,  because  of  the 
general  similarity  in  the  properties  of  these  two  substances.  In 
confirmation  of  this  impression,  it  was  found  that  by  the  oxida- 
tion of  chrysophenol  an  acid  was  obtained  which,  on  distillation 

9 


130         THE   BRITISH   COAL-TAR   INDUSTRY 

with  lime,  gave  a  pyridine  base.  I  need  hardly  remind  you 
that  picoline,  which  was  obtained  from  the  acid  resulting  from 
the  extreme  oxidation  of  flavenol,  is  methylpyridine.  It  was 
thus  established  that  chrysaniline  was  a  derivative  of  a  quinoline 
base. 

The  next  step  in  the  investigation  is  a  very  important  one. 
By  decomposing  the  diazo  compound  of  chrysaniline  with 
alcohol  according  to  the  Griess  reaction,  phenylacridine  was 
obtained.  Acridine  is  a  base  belonging  to  the  quinoline  series, 
having  the  formula  C13H9N.  It  was  discovered  by  Graebe  and 
Caro  in  1872  in  crude  anthracene.  Phenylacridine  accordingly 
possesses  the  formula  Ci3H8N  .  C6H5  ;  and  chrysaniline  appears 
as  diamidophenylacridine — Ci3H7(NH2)N  .  C6H4(NH2),  because 
two  amido  groups  are  replaced  by  H  by  the  diazo  reaction. 
Thus  the  formula  C2oH17N3  (first  assigned  by  Hofmann  to 
chrysaniline)  is  really  the  formula  of  the  higher  homologue, 
chrysotoluidine. 

In  order  to  explain  the  formation  of  chrysaniline  during  the 
oxidation  of  the  materials  (aniline  and  toluidine)  in  the  "  red 
melt "  still,  several  suggestions  were  put  forward,  of  which  the 
most  probable  appeared  to  be  that  the  base  was  derived  from 
triamidotriphenylmethane,  the  latter  compound  resulting  from 
the  condensation  of  two  molecules  of  aniline  with  one  of  ortho- 
toluidine  : 

/NH2 
C6H/         +  2C6H5 .  NH2  -  2H2  =  HC(C6H4NH2)3 

C^Hg  Triamidotriphenyl- 

methane. 


/Ni  H2  /Nv 

C6H/  =C6H4<  |  >C6H3.NH2 

\CH.HjC6H3.NH2-2H2  \C/ 

I'  C6H4.NH2 

C6H4.NH2 

Triamidotriphenylmethane.  Diamidophenylacridine 

=  Chrysaniline. 

The  relationship  of  chrysaniline  to  the  colouring  matters  of 
the  rosaniline  group  is  thus  indicated  ;  but,  tempting  as  is  this 
theme,  time  will  not  admit  of  further  digression  into  this  field. 
The  main  point,  so  far  as  we  are  at  present  concerned,  is  that 
by  means  of  the  present  investigation  we  have  now  arrived  at 
a  knowledge  of  the  parent  substance,  acridine,  of  which  a 
colouring  matter  more  than  twenty  years  old  proves  to  be  a 


SCIENTIFIC  DEVELOPMENT  OF  THE  INDUSTRY  131 

derivative.  By  such  results  new  fields  of  investigation  are 
opened  up,  and  direct  methods  for  the  production  of  chrysaniline 
suggest  themselves.  Even  the  practical  requirements  would  be 
satisfied  if  it  could  be  shown  that  the  colour  could  be  manu- 
factured cheaply  by  a  direct  synthesis,  instead  of  depending,  as 
heretofore,  upon  the  small  and  capricious  secondary  product  of 
the  magenta  manufacture.  As  a  matter  of  fact,  several  syntheses 
of  chrysaniline  have  been  effected,  one  of  which  forms  the  sub- 
ject of  a  patent  (German  patent,  29142,  April  1884)  by  Messrs 
Ewer  &  Pick,  of  Berlin.  Into  the  mode  of  preparation  by 
this  patented  process  I  cannot  now  enter  any  further  than  by 
merely  stating  that  nitrodiphenylamine  and  nitrobenzoylchloride 
form  the  starting-points,  and  that  the  specification  bears  the 
title,  "  preparation  of  chrysaniline  and  other  colouring  matters 
of  the  phenylacridine  group."  If  an  elaborate  scientific  in- 
vestigation culminates  in  a  patent,  its  utility  will,  I  know,  be 
conceded  by  many  for  whom  the  work  would  otherwise  have 
possessed  no  particular  interest. 

The  illustration  which  I  have  given  is  a  typical  example  of 
the  kind  of  scientific  development  which  is  being  carried  on  by 
our  chemical  colleagues  abroad,  and  which  is  being  taken  ad- 
vantage of  in  the  Continental  factories.  I  do  not  wish  to  give 
you  the  impression  that  the  particular  colouring  matters  dealt 
with  are  of  supreme  importance  industrially — they  are  of  con- 
siderable importance,  but  the  modern  history  of  any  other 
colouring  matters  would  have  been  equally  instructive.  The 
beautiful  researches  of  Bernthsen  upon  the  constitution  of 
methylene  blue  would  have  done  equally  well  had  time  per- 
mitted of  my  making  use  of  them. 

It  was  stated  at  the  commencement  of  this  paper  that  there 
is  reason  to  believe  that  our  supremacy  in  the  coal-tar  colour 
industry  has,  for  some  years,  been  declining,  and  I  have  further 
expressed  my  belief  that  the  chief  cause  of  this  falling  off  is  the 
subordinate  position  given  to  chemical  science  in  this  country  as 
compared  with  the  status  of  this  science  abroad.  Whether  this 
explanation  be  accepted  or  not,  the  fact  of  the  decadence  of  the 
manufacture  remains,  and  I  am  in  a  position  to  bring  this  un- 
pleasant truth  home  to  our  countrymen  by  a  strong  body  of 
evidence.  It  must  be  borne  in  mind  that  the  decline  of  any 
industry  cannot  be  measured  by  the  absolute  weight  of  the 
products  turned  out  annually,  because  the  demand  for  the  pro- 


1 32         THE   BRITISH   COAL-TAR   INDUSTRY 

ducts  in  question  may  be  on  the  increase,  and  we  may  be 
actually  producing  a  greater  weight  of  colours  now  than  we 
were  during  our  most  successful  period.  The  whole  question 
is  a  relative  one  :  it  is  simply,  how  much  material  are  we  now 
turning  out  as  compared  with  the  amount  produced  by  our 
competitors — what  proportion  of  coal-tar  products  do  we  supply 
for  our  own  and  foreign  consumption  ?  In  order  to  answer 
this  question  with  some  approach  to  numerical  exactness,  it 
occurred  to  me  that  the  most  trustworthy  information  could 
be  obtained  from  the  consumers  themselves  ;  and  through  the 
kindness  of  Mr  Robert  Pullar,  of  Perth,  and  Mr  Ernest 
Hickson,  of  Bradford,  I  have  been  enabled  to  put  myself  into 
communication  with  several  of  the  representative  dyeing  and 
printing  establishments  of  this  country.  The  facts  obtained,  as 
showing  the  actual  state  of  the  industry  at  the  present  time, 
appear  to  me  of  sufficient  interest  to  be  given  here  in  some 
detail.  I  may  take  the  present  opportunity  of  stating  that  my 
application  for  statistical  information  has  been  most  courteously 
responded  to  by  the  various  firms,  to  whom  I  have  great 
pleasure  in  returning  my  thanks. 

Edward  Ripley  &  Son,  of  Bradford,  perhaps  the  largest 
dyers  of  piece  goods  in  the  kingdom,  inform  me  that  during  the 
year  1885  they  used  86J  per  cent,  of  foreign  coal-tar  colours, 
and  13^  per  cent,  of  English  make. 

Walter  Walker  &  Son,  of  Dewsbury,  dyers  of  wool  for 
rugs,  mats,  carpet  yarn,  and  blanket  stripes,  estimate  that  during 
1885  they  used  80  per  cent,  of  German  dyes.  They  state  that 
the  exact  proportion  is  difficult  to  estimate,  so  that  the  figure 
given  is  only  approximative.  Referring  to  their  larger  con- 
sumption of  foreign  colour,  they  state  :  "  It  is  very  discouraging 
to  have  to  do  this  and  send  the  trade  out  of  our  country,  but 
to  our  own  interest  and  advantage  we  have  to  do  it." 

John  Newton,  silk  dyer,  Macclesfield.  Mr  Walter  Newton, 
F.C.S.,  informs  me  that  during  1885  they  used  80  per  cent,  of 
foreign  colour.  He  adds  :  "  The  rapid  advancement  in  the 
improved  manufacture  of  some  of  these  dyes  by  the  Germans 
is  the  only  cause  of  our  desertion  from  the  English  colour 
manufacturer." 

G.  W.  Oldham,  silk  dyer,  of  Netherton,  near  Huddersfield, 
informs  me  that  during  1885  he  used  2000  Ibs.  of  German  dyes, 
1 100  Ibs.  of  English  dyes,  and  800  Ibs.  of  doubtful  origin. 


SCIENTIFIC  DEVELOPMENT  OF  THE  INDUSTRY  133 


James  Templeton  &  Co.,  of  Glasgow,  state  that  they  dye 
as  much  as  30,000  Ibs.  of  yarn  (chiefly  worsted)  weekly,  but 
they  use  only  a  small  proportion  of  coal-tar  dyes,  all  of  which 
are  of  German  manufacture. 

Messrs  Leckie  &  MacGregor,  of  Paisley,  inform  me 
that  in  the  west  of  Scotland,  including  Glasgow  and  Paisley, 
they  are  certain  that  at  least  90  per  cent,  of  the  dyes  used  come 
from  the  Continent.  Their  own  consumption  of  English  colour 
only  reached  6*8  per  cent. 

Alexander  Harvey  &  Son,  of  Glasgow,  yarn  dyers,  state 
that  during  1885  they  used  60  per  cent,  of  German  and  40  per 
cent,  of  English  dyes.  These  figures  do  not  include  alizarin,  of 
which  they  state  that  they  used  about  equal  quantities  of 
German  and  English  make.  The  English  supply  is  chiefly 
made  up  of  one  article,  "  aniline  salt."  They  add  :  "  We  find 
the  German  makes  in  general  of  better  value  than  the  British,  as 
our  rule  is,  ceteris  paribus,  to  give  the  home-make  the  preference." 

Messrs  Manson  &  Henry,  Glasgow,  yarn  dyers,  state  that 
they  use  only  German  dyes,  adding  that  they  find  it  to  their 
advantage  "for  both  cheapness  and  quality." 

Among  the  largest  consumers  of  coal-tar  colours  in  this 
country  are  the  jute  dyers.  As  representing  this  department  of  the 
tinctorial  industry,  Messrs  James  Stevenson,  of  Dundee,  inform 
me  that  during  1885  they  used  only  7*7  per  cent,  of  English 
colour.  They  have  been  good  enough  to  supply  the  following 
analysis  of  their  consumption  : — 

per  cent.,  of  which  nothing  is  English. 

6-4 
nothing 

nothing 


Scarlet    . 

37    perc 

Crimson 

16 

Blues     . 

ii-5       » 

Oranges 

ii 

Greens  . 

7 

Magenta  (resi 

dues) 

6  *5 

Maroon 

5'5 

Pink 

2-75 

Brown 

I>25 

Violet 

i 

Various 

°'S 

100*0 


1-25 

nothing 


77 


Messrs  Cox  Bros.,  of  the  Camperdown  Jute  Works,  Lochee, 
state  that  practically  the  whole  of  the  "  aniline  "  colours  used  by 
them  are  of  Continental  manufacture. 


134         THE   BRITISH    COAL-TAR   INDUSTRY 

With  reference  to  the  calico-printers,  the  following  facts  have 
been  collected  : — 

Messrs  Z.  Heys  &  Sons,  of  Barrhead,  state  that  during 
1885  they  used  over  10,000  Ibs.  weight  of  colours  (exclusive  of 
alizarin),  of  which  700  Ibs.  only  were  of  English  make. 

Messrs  James  Black  &  Co.,  of  Bonhill,  Dumbartonshire, 
state  that  in  their  belief  more  than  one-half  of  the  colour  used 
by  calico-printers  is  of  foreign  manufacture. 

In  the  course  of  the  present  inquiry  it  seemed  desirable  to 
obtain  information  concerning  the  consumption  of  alizarin,  with 
reference  to  which  the  following  statements  have  been  received : — 

O 

Messrs  Walter  Crum  &  Co.,  of  Thornliebank,  Glasgow,  are 
of  opinion  that  "  the  great  bulk  of  what  is  used  in  this  country 
is  manufactured  in  Germany."  They  do  not  profess  to  be  able 
to  give  actual  figures  having  any  approach  to  accuracy. 

Mr  John  Christie,  of  the  Alexandria  Turkey-Red  Works, 
Dumbartonshire  (John  Orr-Ewing  &  Co.),  states  that  they  use 
only  artificial  alizarin  in  their  establishment,  their  consumption 
being  considerably  over  two  million  Ibs.  weight  of  10  per  cent, 
paste  annually.  Their  consumption  was  in — 

1880  .  98  per  cent.  German.  2  per  cent.  English. 

9°          ?>  »  *         »  »j 

100  o 


1881  . 

1882  . 

1883  . 

1884  . 

1885  . 


77  »  »  23 


56          i»  »'  44 

47          >,  „  53 


Messrs  William  Stirling  &  Sons,  of  Glasgow,  state  that 
their  relative  consumption  of  English  and  German  alizarin  for 
Turkey-red  dyeing  varies  so  much  from  year  to  year  that  they 
have  no  means  of  directly  supplying  useful  data.  This  firm  has, 
however,  been  good  enough  to  make  inquiries  for  me  from  a 
competent  authority,  who  has  furnished  the  following  report  :— 

"In  1883  and  1884,  I  estimate  that  the  sales  (of  alizarin)  in 
the  United  Kingdom  amounted  to  a  monthly  average  of  about 
530  tons,  10  per  cent,  (say,  6360  tons,  10  per  cent,  per  annum). 
Of  this  quantity,  I  estimate  about  30-33  per  cent,  was  manu- 
factured in  this  country.  Taking  1884  alone,  the  figures  are 
estimated  at  566  tons,  10  per  cent,  per  month  (say,  6800  tons, 
10  per  cent,  per  annum).  Proportion  manufactured  in  Great 
Britain,  say,  about  30-35  per  cent.  In  1886,  the  consumption 
may  be  estimated  at  550-600  tons,  10  per  cent,  per  month  (say, 


SCIENTIFIC  DEVELOPMENT  OF  THE  INDUSTRY  135 

6900  tons,  10  per  cent,  per  annum).  Proportion  manufactured 
in  this  country  probably  now  very  considerably  more  than 
35  per  cent." 

This  estimate  of  the  total  consumption  (550  —  600  tons, 
10  per  cent,  per  month)  is  confirmed  by  my  friend  Mr  Thomas 
Royle,  F.C.S.,  of  the  British  Alizarin  Company's  works  at 
Silvertown,  but  he  is  of  opinion  that  50  per  cent,  of  this  is  of 
English  manufacture. 

By  way  of  further  confirmation,  it  appeared  to  me  to  be 
desirable  to  get  the  opinion  of  manufacturers  themselves,  and 
although  this  has  been  a  matter  of  considerable  difficulty,  I  am 
able  to  give  some  kind  of  an  estimate.  Mr  Ivan  Levinstein,  of 
Manchester,  estimates  that  Germany  produces  : 

Colours  derived  from  benzene  and  toluene,  six  times  more 
than  England. 

Colours  derived  from  naphthalene,  seven  times  more  than 
England. 

Colours  derived  from  anthracene,  five  times  more  than 
England. 

The  average  production  of  Germany  is  thus  about  six  times 
that  of  this  country.  Mr  W.  A.  Mitchell,  of  the  firm  of  W.  C. 
Barnes  &  Co.,  Phoenix  Works,  Hackney  Wick,  informs  me  that 
of  some  159  tons  of  "aniline"  dyes  which  passed  through  their 
hands  as  agents  last  year,  95  per  cent,  were  of  Continental  make. 
With  reference  to  the  two  chief  raw  materials,  benzene  and 
aniline,  this  same  firm  estimates  that  about  75  per  cent,  of  the 
whole  quantity  of  these  products  made  in  England  goes  to  the 
Continent.1 

The  facts  and  figures  which  I  have  now  laid  before  you  must 
be  left  to  tell  their  own  story — time  will  not  permit  me  to 
attempt  any  analysis  of  them.  The  evidence  collected  will  at 
any  rate  give  a  much  more  forcible  idea  of  the  true  state  of 
the  coal-tar  colour  industry  in  this  country  than  has  hitherto 
been  attempted,  and  if  this  evidence  goes  against  us  as  a 
manufacturing  nation,  it  is  all  the  more  desirable  that  our  true 

1  According  to  a  later  estimate,  kindly  supplied  by  Mr  Ivan  Levinstein 
the  quantity  of  benzene  and  toluene  used  in  this  country  amounts  to  about 
half  a  million  gallons,  and  that  used  in  Germany  to  about  two  million 
gallons  annually.  About  half  the  English  production  is,  however,  exported 
as  aniline,  toluidine,  and  aniline  salt,  while  Germany  converts  into  colouring 
matters  at  least  1,600,000  gallons  of  these  hydrocarbons. 


136         THE  BRITISH    COAL-TAR   INDUSTRY 

position  should  be  realised.  I  find  that  it  is  almost  impossible 
to  give  a  correct  numerical  expression  in  pounds  sterling  for 
the  annual  value  of  this  industry  to  the  country,  as  the  estimates 
vary  within  very  wide  limits.  According  to  Dr  Perkin,  whose 
opinion  on  this  matter  will  perhaps  carry  the  greatest  weight, 
the  value  of  the  annual  output  is  between  ^3,000,000  and 
^4,000,000.  That  the  industry  is  one  of  considerable  import- 
ance on  the  Continent  may  be  gathered  from  the  official  returns 
relating  to  the  German  exports.  For  the  following  figures  1 
am  indebted  to  Dr  H.  Caro,  of  the  Badische  Anilin-  und 
Soda-Fabrik,  Ludwigshafen  on  Rhine  : — 

EXPORTED  FROM  GERMANY,  FROM  JANUARY  i  TO  DECEMBER  31,   1885. 

Alizarin  paste  (?  per  cent.)      .         .         .     4283  tons. 
Aniline  and  intermediate  products .         .     1713     „ 
Aniline,  etc.,  colours      ....     4645     „ 

Dr  Caro  adds  that  it  is  generally  believed  that  about  four- 
fifths  of  the  entire  German  production  are  exported. 

The  magnitude  of  this  branch  of  chemical  industry  abroad 
will  be  gathered  from  the  fact  that  a  German  factory  of  about 
the  third  magnitude  consumes  at  the  present  time  between  500 
and  600  tons  of  aniline  annually.  According  to  information 
recently  furnished  to  me  from  the  two  largest  of  the  German 
factories,  the  Badische  Company  employ  2500  working  men  and 
officials,  and  the  Hoechst  Colour  Works  (formerly  Meister, 
Lucius  &  Brttning)  1600  working  men  and  fifty-four  chemists. 
It  must  of  course  be  borne  in  mind  that  in  these  factories  the 
products  are  not  "aniline"  colours  only,  but  alizarin,  acids, 
alkalies,  and  all  chemicals  required  in  this  branch  of  manufacture. 

The  industry  which  has  been  selected  for  this  evening's  topic 
is  thus  not  only  an  important  one  in  itself,  but  for  us,  as 
chemists,  its  development  is  fraught  with  meaning  both  scienti- 
fically and  educationally.  In  taking  up  this  subject  it  has  not 
been  my  desire  to  exalt  the  coal-tar  colour  industry  to  a  position 
of  undue  importance,  nor  do  I  wish  it  to  be  inferred  that  the 
remarks  which  I  have  made  concerning  its  decadence,  or  at  any 
rate  stagnation,  in  this  country  are  applicable  to  this  manu- 
facture only.  The  failure  on  our  part  to  grasp  the  true  spirit 
of  chemical  science  in  its  relation  to  our  manufactures  makes 
itself  felt  in  every  industry  in  which  chemistry  is  concerned. 
The  strength  of  our  competitors  is  in  their  laboratories,  and 


SCIENTIFIC  DEVELOPMENT  OF  THE  INDUSTRY  137 

not,  as  here,  upon  the  exchanges.  It  is  only  by  showing  up 
our  weakness  in  each  industry  that  the  state  of  affairs  can  be 
remedied,  and  our  prestige  as  a  manufacturing  country  restored. 
If  each  specialist  would  do  for  his  industry  what  I  have  here 
attempted  to  do  broadly  for  the  coal-tar  colour  industry,  we 
should  get  together  a  body  of  evidence  which  the  Royal  Com- 
missioners on  the  depression  of  trade  would  do  well  to  take  into 
consideration.  We  have  heard  a  great  deal  of  late  years  about 
the  subject  of  technical  education,  but  the  talk  has  been  rather 
one-sided.  We  have  had  utterances  from  those  who,  recognising 
the  enormous  importance  of  this  subject  to  the  country,  have 
munificently  endowed  those  institutions  for  the  promotion  of 
technical  education  which  are  springing  up  around  us  ;  we  have 
had  all  kinds  of  schemes  from  those  who  are  taking  upon  them- 
selves the  duties  of  technical  educators  ;  but  it  appears  to  me 
that  we  have  not  heard  with  sufficient  distinctness  the  voices  of 
those  who  may  be  presumed  to  suffer  most  from  the  want  of 
technical  education,  viz.  the  manufacturers  themselves.  I  have 
heard  rumours  of  the  existence  of  a  certain  class  of  manufacturer 
— let  us  hope  a  rare  species — who  declares  that  science  is  no  use 
to  him,  and  that  he  can  get  along  better  without  it.  I  must 
confess  that  I  never  met  this  individual  in  the  flesh,  but  I  know 
that  he  exists  in  some  of  our  manufacturing  centres.  As  a 
species  he  is,  however,  doomed  to  extinction  in  the  struggle 
with  his  competitors,  and  we  may  consider  him  out  of  court  in 
the  discussion  of  schemes  of  technical  Education.  It  is  now 
generally  admitted  that  the  days  of  empiricism  have  passed 
away,  and  most  manufacturers  admit  that  present  success  and 
future  development  depend  upon  a  proper  recognition  of 
technical,  i.e.  of  applied,  science.  But  unless  the  manufacturers 
themselves  speak  loudly  on  this  question,  the  voices  of  those 
who  wish  to  promote  scientific  education  may  be  drowned  by 
the  clamour  of  mere  theorists. 

In  no  other  department  of  our  manufactures  is  the  want  of 
technical  science  more  felt  than  in  the  chemical  industries.  We 
not  only  see  this  in  the  greater  development  of  these  industries 
abroad,  but  in  some  of  our  most  successful  factories  here — and 
this  applies  more  especially  to  the  coal-tar  colour  industry — 
foreign  chemists  are  employed,  and,  as  I  have  lately  been  informed 
by  a  well-known  manufacturer,  it  is  even  impossible  to  get  the 
necessary  plant  properly  made  in  this  country.  There  is  no 


138         THE   BRITISH    COAL-TAR   INDUSTRY 

doubt  that  the  recondite  character  of  the  truths  of  chemical 
science,  as  compared  with  the  more  obvious  truths  of  mechanics 
and  physics,  has  much  to  do  with  the  want  of  popularity  of  this 
branch  of  knowledge,  and  is  responsible  for  the  circumstance 
that  our  science  is  regarded  with  comparative  indifference  until 
some  branch  of  manufacture  is  in  extremis.  In  our  national 
characteristic  of  being  "  practical,"  we  are  apt  to  become  short- 
sighted in  our  manufacturing  policy,  and  to  recognise  only 
actualities  to  the  exclusion  of  the  potentiality  conferred  upon  a 
nation  by  a  broader  scientific  culture. 

DISCUSSION 

Mr  R.  J.  FRISWELL  said,  the  great  difficulty  scientific  men  had 
to  encounter  was  to  persuade  those  whose  money  interest  placed 
them  at  the  head  of  large  factories  that  scientific  work,  the  practi- 
cal outcome  of  which  was  not  immediately  visible,  was  really  of 
value.  It  was  a  long  struggle,  but  he  thought  they  were 
beginning  to  see  daylight  at  last.  A  feeling  was  beginning  to 
be  awakened,  not  in  the  coal-tar  colour  industry  alone,  but  in 
others  also,  and  he  thought  the  coming  generation  of  manu- 
facturers would  take  to  heart  the  lesson  which  Professor  Meldola 
and  others  had  so  strongly  enforced,  so  that  in  the  course  of  a 
few  years  a  great  change  would  be  seen  in  this  direction.  What 
had  been  said  with  regard  to  the  alizarin  industry  showed  that 
already  in  that  direction  a  very  marked  change  was  beginning  to 
take  place,  and  he  hoped  it  would  not  be  many  years  before  they 
saw  a  change  in  the  same  direction  in  other  coal-tar  colours. 
Every  Englishman  must  feel  that  it  was  a  great  reproach  to  this 
country  that  an  industry  which  originated  here  should  so  far 
have  slipped  out  of  her  grasp. 

The  Chairman  (Professor  JAMES  DEWAR)  said  he  desired  most 
heartily  to  thank  Professor  Meldola  because  he  had  not  in  any 
way  feared  to  tell  the  whole  truth.  When  such  a  statement 
came  from  a  man  who  had  not  confined  himself  purely  to  the 
scientific  side  of  the  question,  but  who  had  been  himself  superior 
chemist  in  a  large  works,  it  showed  that  he  was,  from  his  thorough 
knowledge  of  both  sides  of  the  question,  entitled  to  speak  in  this 
bold  and  straightforward  way.  He  must  differ  from  the  writer 
of  the  paper  on  one  point,  where  he  said  he  had  never  met  the 
manufacturer  who  declined  to  say  that  science  was  a  great  bene- 


SCIENTIFIC  DEVELOPMENT  OF  THE  INDUSTRY  139 

factor.     On  two  occasions  in  his  life  he  had  certainly  had  this 
experience.     At  one  time,  when  a  young  man,  he  was  offered 
the  same  position  that  Professor  Meldola  held  for  several  years, 
and    the    difficulty  which  arose  was    entirely  with    reference  to 
supplying  the  laboratory.     On  another  occasion  a  similar  diffi- 
culty arose  with  a  very  distinguished  man,  in  which  he  projected 
something  of  the  same  kind,  but  the  moment  he  began  to  ask 
where  the    materials  were,  and  where   the   laboratory  was,  the 
engagement  was  abruptly  broken  off,  as  this  gentleman  saw  no 
reason  for  having  a  laboratory  in  connection  with  the  work  at 
all.     There  was  the  difference.     It  was  not  only  the  stimulus  in 
the  large  German  laboratories,  where  active  research  was  going 
on,  but  it  was  the  large  stimulus  now  existent  among  the  factories 
themselves.     There  the  men  were  not  isolated,  but,  as  they  had 
heard,  there  were  something   like    fifty  chemists    in    one  large 
factory,  so  that  there  was  a  little  scientific  world  in  itself,  where 
there  was  an  incentive  to  continuous  work.     With  reference  to 
the  question  as  to  the  want  of  popularity  in  chemical  science,  he 
admitted  it,  of  course,  but  the  question  was,  what  was  the  full 
explanation  of  it  ?     He  thought  it  arose  in  a  great  degree  from 
the  want  of  encouragement  of  chemistry  in  the  older  universities. 
He  said  so,  not  because  the  older  universities  sent  out  a  larger 
number  of  men  than  the  young  ones,  but  simply  because  up  to 
the  present  time  they  had  no  such   thing  as  even  a  creditable 
chemical  laboratory.     Although  he  held  the  chair  in  one  of  these 
universities,  he  was  always  ashamed  if  anyone  asked  to  see  the 
chemical  laboratory,  because,  in  truth,  there  was  none.     It  was 
in  the  same  condition  as  it  was  a  century  ago.     If  you  got  a  pupil 
out  of  the  mass  who  showed  some  originality,  you  found  you 
could  not  retain  him,  you  had  not  the  materials  or  the  money, 
and  consequently  he  went  to  some  large  German  laboratory  where 
material  was  to  be  had,  and  where  his  work  was  encouraged.     As 
long  as  that  went  on,  how  could  the  science  be  popular  ?     Another 
important  point  in  the   paper  was  the  proof  of  the  marvellous 
result  of  action  and  reaction.     Of  course,  as  a  physical  principle, 
that  was  admitted  on  all  hands  to  be  an  elementary  truth,  but  all 
these  facts  now  brought  forward  had  had  the  most  remarkable 
effect  as  a  stimulus  on  the  growth  of ; the  more  recondite  scientific 
investigation  ;  every  new  success  connected  with  any  colour  which 
might  be  discovered  was  a  stimulus  to  further  investigation,  and 
the  result  was  that  all  the  marvellous  group  of  colouring  matters 


140         THE   BRITISH   COAL-TAR   INDUSTRY 

were  now  to  be  had  in  such  enormous  quantity  that  the  chemist 
got  numerous  new  foci  from  which  to  start  fresh  investigations. 
Consequently,  all  this  industry  had  conversely  affected  chemical 
laboratories,  purely  scientific,  by  the  supply  of  splendid  new 
material. 

Mr  LIGGINS  said  it  was  impossible  to  overestimate  the 
brilliancy  and  beauty  of  these  coal-tar  dyes,  or  to  give  too  much 
praise  to  those  chemists  who  had  invented  the  processes  which 
had  given  such  brilliant  results,  and  as  an  artist  he  must  say 
it  was  impossible,  either  with  oil  or  water-colour,  to  produce 
colours  of  such  beautiful  shades  as  some  of  those  which  were 
exhibited  ;  but  there  were  two  sides  to  every  question,  and 
several  times  within  the  last  few  weeks  the  most  thorough  con- 
demnation of  aniline  dyes  had  been  pronounced  in  that  room 
by  able  men  and  scientific  men,  especially  in  connection  with 
the  artistic  work  of  Japan  and  India.  The  carpets  of  India 
were  said  to  be  ruined  by  aniline  colours  which  were  used  in 
dyeing,  and  it  was  said  to  be  one  of  the  greatest  misfortunes  for 
India  that  these  colours  had  been  introduced,  as  they  were  very 
inferior  to  those  the  natives  had  been  for  centuries  in  the  habit 
of  using  ;  besides  that,  it  was  very  commonly  supposed  that  the 
colouring  matters  of  various  articles  of  clothing  were  poisonous. 

Professor  MELDOLA  said,  with  regard  to  the  fugitiveness  of 
these  colours,  there  was  a  great  deal  of  misapprehension,  and  the 
same  with  regard  to  the  poisonous  character  of  the  dyes.  A 
great  controversy  had  been  carried  on  lately  in  Bradford  before 
the  Society  of  Dyers  and  Colourists.  Specimens  had  been  sub- 
mitted to  careful  analysis,  in  order  to  detect  arsenic,  because  it 
was  known  that  some  of  these  colours  were  made  by  means  of 
arsenic  acid,  and  it  was  thought  they  might  retain  traces  which 
rendered  them  poisonous  ;  but  the  amount  found  was  infinitesi- 
mal. No  doubt  many  of  these  colours  were  fugitive,  but,  on  the 
other  hand,  some  of  the  alizarin  colours,  which  were  used  for 
dyeing  carpet  yarn,  would  bear  exposure  to  light,  and  remain 
unaltered  long  after  the  old  vegetable  colours  had  faded  com- 
pletely away. 


IX.:     i896 

THE  ORIGIN   OF  THE  COAL-TAR  COLOUR 

INDUSTRY,  AND  THE  CONTRIBUTIONS  OF 

HOFMANN  AND  HIS  PUPILS 

BY  W.  H.  PERKIN,  PH.D.,  D.C.L.,  F.R.S. 

(Hofmann  Memorial  Lecture  :  Journal  of  the  Chemical  Society^  1896,  p.  596) 

THE  illustrious  man  whose  lifework  we  are  called  on  to  com- 
memorate was  well  known  to  very  many  of  us,  especially  those 
who  had  the  privilege  of  being  his  students  and  assistants.  We 
can  all  recall  the  pleasure  and  interest  with  which  we  listened  to 
the  lucid  and  graphic  accounts  of  his  researches  which  he  used 
to  bring  before  the  Chemical  Society  in  years  gone  by  ;  and 
great  was  felt  to  be  the  loss,  not  only  to  us,  but  also  to  the 
country,  when  he  left  it  for  his  fatherland  :  but  now  we  mourn 
a  far  greater  loss,  and  one  which  we  realise  more  and  more 
deeply  as  we  consider  the  incidents  of  his  remarkable  career — a 
career  of  such  incessant  activity  and  brilliant  achievement. 

I  am  charged  with  a  duty  which  I  wish  had  been  placed  in 
more  capable  hands  than  mine  :  to  give  an  account  of  the  rise 
and  progress  of  the  coal-tar  colour  industry,  and  its  relation  to 
the  Hofmann  school ;  and,  as  being  connected  with  its  com- 
mencement, I  am  requested  to  make  the  account  to  a  large 
extent  autobiographical — a  part  of  my  task  which  it  would  have 
been  more  agreeable  to  me  to  have  seen  undertaken  by  others 
rather  than  myself. 

This  industry  holds  an  unique  position  in  the  history  of 
chemical  industries,  as  it  was  entirely  the  outcome  of  scientific 
research.  We  have  to  go  back  to  1825,  when  Faraday  discovered 
benzene,  or,  as  he  then  termed  it  "  bicarburetted  hydrogen,"  for 
the  first  investigation  which  clearly  bears  upon  the  subject. 

141 


i42         THE   BRITISH   COAL-TAR   INDUSTRY 

Faraday  separated  the  hydrocarbon  from  the  liquid  products 
condensed  on  compressing  the  gas  obtained  from  oil.  A  year 
later  (1826),  Unverdorben  obtained  aniline  by  the  mere  distilla- 
tion of  indigo,  and  called  it  "  crystalline."  Runge  afterwards 
obtained  it  from  coal-tar  oil,  and  having  observed  that  it  produced 
a  violet-blue  coloration  with  chloride  of  lime,  called  it  "  kyanol." 
It  was  subsequently  obtained  from  indigo  by  Fritsche  by  distilling 
this  colouring  matter  with  caustic  alkali.  We  then  come  to  the 
important  work  of  Mitscherlich,  who  obtained  the  hydrocarbon 
benzene  from  a  new  source,  namely,  benzoic  acid, — whence  the 
name,  and  produced  from  this  nitrobenzene.  Zinin  subsequently 
found  that  benzidam,  as  he  termed  it,  could  be  produced  by  the 
action  of  sulphuretted  hydrogen  in  presence  of  ammonia  on  an 
alcoholic  solution  of  nitrobenzene. 

This  brings  us  to  the  commencement  of  Hofmann's  researches 
on  aniline,  a  substance  which  he  used  sometimes  to  speak  of  as  his 
"  first  love."  In  his  first  published  paper  he  showed  that  Unver- 
dorben's  crystalline,  Runge's  kyanol,  Fritsche's  aniline,  and  Zinin's 
benzidam  were  all  the  same  compound,  for  which  he  afterwards 
selected  Fritsche's  name,  aniline.  Later  on,  Hofmann  and 
Muspratt  prepared  toluidine  from  toluene  from  tolu  balsam. 

The  work  on  the  separation  of  aniline  from  tar  was  done 
before  the  date  of  Hofmann's  coming  to  this  country,  viz.  in 
1 843.  After  his  arrival  here  in  1 845,  he  continued  his  researches, 
and,  to  realise  something  of  his  indomitable  perseverance,  it  is 
necessary  to  remember  that,  until  the  coal-tar  colour  industry 
was  established,  practically  all  the  aniline  he  used  in  his  numerous 
inquiries  was  procured  by  the  laborious  and  costly  process  of 
distilling  indigo  with  potash. 

In  1843,  organic  chemistry  was  still  in  its  infancy,  and  coal- 
tar  naphtha  had  not  yet  been  investigated.  Runge  had  isolated 
carbolic  acid,  pyrrol,  kyanol  or  aniline,  and  leucol  or  quinoline. 
Naphthalene  was  well  known  to  exist  in  tar,  having  been  separated 
by  Garden,  as  early  as  1820.  Dumas  had  discovered  para- 
naphthalene  or  anthracene,  and  chrysene  and  pyrene  had  been 
referred  to  by  Laurent,  but  these  were  very  doubtful  compounds. 
This  was  about  all  that  was  known  of  the  composition  of  coal-tar 
at  that  time.  Hofmann  showed,  in  1845,  tnat  benzene  must 
exist  in  the  naphtha,  as  he  found  that  aniline  could  be  produced 
from  it,  but  he  never  separated  this  hydrocarbon  ;  shortly  after- 
wards, however,  he  induced  his  pupil,  Charles  Mansfield — of 


HOFMANN    MEMORIAL  LECTURE  143 

whom  he  always  spoke  in  the  highest  terms — to  undertake  the 
investigation  of  the  liquid  hydrocarbons  of  coal-tar. 

On  reading  over  the  account  of  Mansfield's  investigation, 
and  bearing  in  mind  that  in  those  days  fractional  distillation  was 
conducted  in  old-fashioned  glass  retorts  with  the  thermometer  in 
the  liquid,  it  is  impossible  not  to  admire  the  patience  and  per- 
severance he  exercised,  as  well  as  the  systematic  and  skilful 
manner  in  which  he  worked. 

All  who  have  undertaken  fractional  distillations,  even  with  all 
our  present  knowledge  and  improved  apparatus,  know  how  diffi- 
cult it  is  to  detect  and  isolate  products  in  a  mixture  such  as  coal- 
tar  naphtha.  Yet  Mansfield  obtained  benzene  in  a  pure  state,  and 
toluene  sufficiently  so  for  Hofmann  to  prepare  toluidine  from  it. 
He  also  obtained  pseudocumene,  and  was  led  to  believe  in  the  exist- 
ence of  xylene.  In  describing  his  work,  he  modestly  remarks  : — 

"  It  has  been  perhaps  the  tedium  of  the  methods  necessary  to 
effect  a  separation  of  mixed  hydrocarbons  from  each  other  which 
has  deterred  experienced  chemists  from  devoting  their  time  to 
disentangling  the  oils  here  treated  off:  and  perhaps  to  have  con- 
ducted the  innumerable  distillations  necessary  for  this  purpose 
in  a  laboratory  imperfectly  furnished  with  gas  and  other  con- 
veniences, would  have  been  a  task  too  laborious  to  have  been 
persisted  in  "  (Jour.  Chem.  Soc.,  1849,  1>  246). 

Amongst  the  inquiries  carried  on  by  Hofmann,  in  the  early 
days  of  the  Royal  College  of  Chemistry,  were  those  classical 
"  researches  regarding  the  molecular  constitution  of  the  volatile 
organic  bases,"  in  which  he  succeeded  in  displacing  the  hydrogen 
of  the  NH2  group  by  different  alcohol  radicles,  eventually  ob- 
taining also  the  ammonium  compounds.  In  the  first  of  these 
(Jour.  Chem.  Soc.,  3,  1851)  he  describes  ethylaniline  (p.  284),  and 
diethylaniline  (p.  288),  also  methylaniline  (p.  295).  The  method 
used  in  these  researches,  of  substituting  hydrogen  in  amines  by 
means  of  the  iodides  and  bromides  of  the  alcohol  radicles,  and 
also  the  substituted  anilines  which  were  obtained,  although  not 
connected  with  the  foundation  of  the  coal-tar  colour  industry, 
have  been  of  great  value  in  its  after  development.  These  few 
references  to  observations  on  the  early  work  carried  on  at  the 
Royal  College  of  Chemistry,  for  the  sake  of  science  only,  show, 
in  fact,  what  valuable  material  was  produced  for  the  coming  new 
industry  ;  indeed,  without  the  research  of  Mansfield,  it  could 
never  have  become  an  industry. 


i44         THE   BRITISH   COAL-TAR   INDUSTRY 

The  foregoing  brings  the  work  of  the  Royal  College  of 
Chemistry  up  to  near  the  date  when  I  became  a  student  there  ; 
and  it  will,  perhaps,  be  well  if  I  here  refer  to  my  young  days, 
and  state  how  it  came  to  pass  that  1  had  the  good  fortune  to 
study  under  Hofmann,  especially  as  it  will  enable  me  to  say  a 
few  words  in  reference  to  one  of  his  old  pupils,  Mr  Thomas 
Hall,  B.A.,  who  has  done  much  for  the  cause  of  science. 

As  long  ago  as  I  can  remember,  the  question  of  what  pursuit  I 
should  follow  was  constantly  before  me.     Even  when  very  young, 
I  interested  myself  in  several  subjects  of  a  mechanical  kind,  and 
worked  at  them  to  the  best  of  my  ability  ;  and  elementary  as  the 
experience  then  gained  was,  it  had  a  lasting  influence  upon  me. 
When  I  was  between  twelve  and  thirteen  years  of  age,  a  young 
friend  was  good  enough  to  show  me  some  chemical  experiments  ; 
amongst  these  were  some  on  crystallisation,  which  seemed  to  me 
most  marvellous  phenomena  :  as  a  result,  my  choice  was  fixed, 
and  it  became  my  desire  to  be  a  chemist,  if  possible,  as  I  saw  that 
there  was  in  this  science  something  far  beyond  the  mechanical 
and   other   pursuits  I  had  been  previously  occupied  with.     At 
this  time  I  left  the  school  I  was  attending,  and  entered  the  City 
of  London  School,  of  which  Dr  Mortimer  was  then  head  master. 
Here  lectures  were  given  on  chemistry  and  natural  philosophy  ; 
indeed,  I  believe  this  was  the  first  school  in  which  experimental 
science  was  taught.     The  lecturer  was  one  of  the  masters,  Mr 
Thomas  Hall,  an  old  student  of  Hofmann's  who  had  obtained 
all  the  chemical  knowledge  he  possessed  by  working  at  the  Royal 
College  of    Chemistry.     To  attend  these  lectures  was  a  source 
of  great  pleasure  to  me.     There  was  also  a  yearly  examination  in 
science,  and  the   examiner  was  also  one  of  Hofmann's  pupils, 
and  his  first  assistant,  none  other  than  my  friend  Mr,  now  Sir, 
Frederick  Abel.     In    the    City  of   London  School    1    was  con- 
sequently brought  directly  under  Hofmannic  influence,  if  I  may 
so  term  it,  for  all  who  came  in  contact  with  those  who  worked 
with  him  had  infused  into  them  by  induction  his  enthusiasm  for 
chemistry.     Mr  Hall  very  soon  took  an  interest  in   me,  and 
installed  me  as  one  of  his  lecture  assistants.     Science,  however, 
was  not  allowed  to  interfere  with  the  ordinary  school  curriculum, 
so  that  the  lectures,  and  the  preparations  for  them,  were  delegated 
to  the  interval  for  dinner,  and  being  very  much  interested  in  pre- 
paring the  experiments,  I  not  unfrequently  found  this  interval 
had  passed  before   I   left  off  work  ;    but,  fortunately,  I   never 


HOFMANN    MEMORIAL  LECTURE  145 

found  that  the  abstinence  thus  caused  acted  prejudicially  upon 
me.  Whilst  with  Mr  Hall,  I  heard  much  of  the  Royal  College 
of  Chemistry  and  its  Professor,  and  after  my  master  had  very 
kindly  had  several  interviews  with  my  father — who  wished  me  to 
be  an  architect  and  not  a  chemist — it  was  my  good  fortune  to 
be  allowed  to  follow  my  bent,  and  go  to  the  Royal  College  of 
Chemistry,  in  Oxford  Street. 

Before  passing  from  my  schooldays,  I  feel  I  must  say  a  few 
more  words  about  my  old  schoolmaster,  to  whose  kindness  I 
owe  so  much.  Thomas  Hall  was  a  born  teacher,  who  took  an 
individual  interest  in  his  scholars,  studying  their  characters,  and 
stimulating  any  special  qualities  he  saw  they  possessed,  and,  at 
the  same  time,  inculcating  the  highest  moral  qualities.  He  hated 
anything  that  was  mean  or  underhand,  and,  at  the  same  time,  was 
very  genial  and  kind-hearted  ;  this  may  be  gathered  from  the 
fact  that  the  boys  used  to  speak  of  him  as  Tommy  Hall.  His 
influence  on  behalf  of  science,  especially  the  science  of  chemistry, 
was  great ;  it  appears,  from  a  list  of  old  City  of  London  School 
boys,  kindly  given  me  by  Mr  John  Spiller,  that  more  than  thirty 
boys  in  whom  he  had  taken  an  interest  afterwards  worked  at  the 
Royal  College  of  Chemistry,  and  of  these  I  may  mention  the 
following  as  having  contributed  papers  to  our  Transactions  : 

J.  J.  Bowrey,  J.  T.  Brown,  Frank  Clowes,  W.  H.  Deering, 
Edward  Divers,  J.  A.  Newlands,  F.  J.  M.  Page,  W.  H.  Perkin, 
Alexander  Pedler,  J.  Spiller,  and  W.  Thorp. 

I  entered  the  Royal  College  of  Chemistry  when  I  was  in  my 
fifteenth  year,  at  the  time  when  that  institution  became  part  of 
the  School  of  Mines,  but  I  only  took  up  the  study  of  chemistry. 
After  seeing  Dr  Hofmann  with  my  father,  the  first  person  I 
encountered  in  the  laboratory  was  the  Assistant,  Mr  W.  Crookes, 
who  set  me  to  study  the  reactions  of  the  metals. 

There  was  no  theatre  at  the  Royal  College  then,  and  the 
students  had  to  go  to  the  Museum  of  Practical  Geology  in 
Jermyn  Street  to  hear  the  lectures  on  chemistry,  which  involved 
a  rather  serious  loss  of  time  ;  but  the  lectures  made  up  for  this, 
as  Hofmann  spared  no  pains  in  making  them  as  interesting,  in- 
structive, and  perfect  as  he  possibly  could,  illustrating,  as  far  as 
practicable,  everything  by  experiment,  so  that  the  facts  were 
firmly  impressed  upon  the  mind.  At  that  time  he  also  had  a 
very  efficient  lecture  assistant,  the  late  Mr  Witt.  Hofmann  was 
good  enough  to  let  me  attend  these  lectures  a  second  time. 

TO 


146         THE   BRITISH   COAL-TAR   INDUSTRY 

When  going  through  the  ordinary  course  of  qualitative  and 
quantitative  analysis,  the  students  working  at  research  appeared 
to  me  to  be  superior  beings,  something  beyond  ordinary  persons  ; 
and  being  possessed  with  a  desire  to  join  their  ranks,  the  ordinary 
course,  and  also  gas  analysis  by  Bunsen's  method,  was  quickly 
gone  through.  Hofmann  then  set  me  to  work  at  research,  and 
very  curiously  gave  me  as  a  subject  the  hydrocarbon  anthracene, 
or,  as  it  was  generally  called  in  those  days,  paranaphthalene.  To 
obtain  this,  pitch  was  taken  as  the  starting-point,  but  as  it  was 
found  that  this  method  of  preparation  was  a  very  tedious  one  to 
carry  out  in  the  laboratory,  Hofmann  kindly  obtained  some  of 
the  crude  product  for  me  from  Mr  Cliff,  of  Bethels  Tar  Works. 
As  is  well  known,  Hofmann — especially  at  that  period — was 
much  interested  in  the  formation  of  organic  bases  from  hydro- 
carbons, and  the  object  of  my  investigation  was  to  produce,  if 
possible,  a  nitro  compound,  and  then  convert  this  into  a  base  by 
reduction.  However,  anthracene  refused  to  give  a  nitro  com- 
pound, and  consequently  no  base  could  be  obtained,  but,  in  the 
course  of  my  work,  I  prepared  the  compound  we  now  know  as 
anthraquinone,  and  also  the  chlorine  and  bromine  derivatives  of 
anthracene.  But  these  substances  could  not  be  got  to  yield  in- 
telligible results  on  analysis,  and  at  that  time  it  never  occurred 
either  to  Hofmann  or  myself  that  there  was  any  likelihood  of 
Dumas  and  Laurent's  formula  for  the  hydrocarbon  (i.e.  C^H^) 
being  incorrect.  The  consequence  was  that  this  research  was 
set  aside,  but  I  shall  show  further  on  that  the  experience  I  then 
gained  was  of  great  importance  to  me  several  years  later,  when  I 
commenced  to  work  at  the  production  of  alizarin. 

Hofmann  next  set  me  to  work  to  study  the  action  of  chloride 
of  cyanogen  on  naphthylamine  in  the  same  way  that  he  had 
examined  the  action  of  this  gas  on  aniline.  In  those  days  there 
were  no  depots  where  pure  products  for  research  could  be  obtained 
as  there  now  are,  and  for  this  inquiry  even  the  naphthalene  had 
to  be  purified  in  the  laboratory  ;  this  research  was  soon  completed, 
but  was  not  written  out  and  published  until  nearly  twelve  months 
afterwards.  It  was  brought  before  the  Chemical  Society  when  the 
meetings  were  held  in  Mr  Pepper's  house  in  Cavendish  Square. 

Hofmann  had  a  marvellous  power  of  stimulating  his  students, 
and  of  imparting  to  them  his  own  enthusiasm  ;  he  took  the 
strongest  personal  interest  in  their  work,  visiting  three  or  four 
times  in  the  week  even  those  who  were  going  through  the 


HOFMANN   MEMORIAL   LECTURE  147 

reactions,  while  those  engaged  in  research  work  were  seen  daily 
by  him,  and  if  anything  of  special  interest  was  going  on,  more 
than  once  in  the  day.  His  power  of  directing  research  was  also 
most  remarkable  ;  with  the  aid  of  a  few  watch-glasses,  a  glass 
rod,  and  a  small  gas  flame  he  would  make  a  number  of  experi- 
ments, and  from  the  information  thus  gained  tell  his  students 
how  to  proceed  with  their  work.  I  well  remember  how  one  day, 
when  the  work  was  going  on  very  satisfactorily  with  most  of  us 
and  several  new  products  had  been  obtained,  he  came  up  and  com- 
menced examining  a  product  of  the  nitration  of  phenol  which  one 
of  the  students  had  obtained  by  steam  distillation  ;  taking  a  little 
of  the  substance  in  a  watch-glass,  he  treated  it  with  caustic  alkali, 
and  at  once  obtained  a  beautiful  scarlet  salt  of  what  we  now  know 
to  be  orthonitrophenol.  Several  of  us  were  standing  by  at  the 
time,  and,  looking  up  at  us  in  his  characteristic  and  enthusiastic 
way,  he  at  once  exclaimed,  "  Gentlemen,  new  bodies  are  floating 
in  the  air."  I  mention  this  just  as  an  example  of  the  way  in 
which  he  used  to  stimulate  us  by  his  own  example. 

After  I  had  completed  the  research  on  the  action  of  chloride 
of  cyanogen  on  naphthylamine,  Hofmann  promoted  me  to  the 
position  of  an  assistant  in  his  research  laboratory  ;  I  was  then 
seventeen  years  of  age.  Mr  A.  H.  Church,  now  Professor 
Church,  was  among  the  assistants  in  the  laboratory.  This  position 
proved  most  valuable  to  me. 

At  this  time  Professor  Cahours  came  over  from  Paris  to  work 
with  Hofmann  on  the  allyl  compounds,  a  research  in  which  Pro- 
fessor Church  and  I  had  to  assist.  They  then  commenced  their 
splendid  work  on  the  phosphorus  bases,  and  I  well  remember  the 
excitement  and  interest  which  prevailed  when  Paul  Thenard's 
triethylphosphine  was  first  produced  by  the  action  of  zinc  ethyl 
on  phosphorus  trichloride,  and  Hofmann's  delight  when  he  found 
it  was  vigorously  acted  on  by  methyl  and  also  ethyl  iodide,  pro- 
ducing white,  crystalline,  phosphonium  iodides.  1  was  occupied 
with  this  research  until  I  left  the  Royal  College. 

I  may  here  refer  to  an  incident  which  shows  how  greatly 
Hofmann  was  interested  in  his  scientific  work.  One  day,  when 
he  was  going  his  usual  rounds  in  the  general  laboratory,  a  student 
standing  not  far  from  him  poured  a  quantity  of  concentrated 
sulphuric  acid  into  a  thick  glass  bottle  he  was  holding  in  his  hand, 
which  contained  a  small  quantity  of  water  ;  the  consequence  was 
that  the  heat  evolved  caused  it  to  crack  and  the  bottom  to  fall 


148         THE   BRITISH   COAL-TAR   INDUSTRY 

out.  Some  of  the  acid  splashed  up  from  the  floor  into  HofmanrTs 
eye,  and  we  feared  would  have  a  permanently  injurious  effect 
upon  it.  Hofmann  was  sent  home  in  a  cab,  and  had  to  be  kept 
in  bed  in  a  dark  room  during  several  weeks,  his  old  friend,  Dr 
Bence  Jones,  attending  him.  But  during  this  time,  and  notwith- 
standing his  sufferings,  he  was  so  anxious  about  his  work  that  we 
used  to  have  to  visit  him  in  his  darkened  bedroom,  to  report 
progress  and  also  to  receive  any  instructions  he  had  to  give. 

Whilst  in  the  research  laboratory  I  had  the  privilege  of  meet- 
ing St  Claire  Deville,  who  came  to  London  for  the  purpose  of 
exhibiting  specimens  of  sodium  and  aluminium  at  a  lecture  given 
by  the  Rev.  T.  Barlow  at  the  Royal  Institution,  of  which  the 
lecturer  was  Secretary. 

Whilst  assistant  under  Hofmann,  I  had  but  little  time  for 
private  work  in  the  daytime  ;  as,  however,  I  wished  to  continue 
research  work,  part  of  a  room  at  home  was  fitted  up  as  a  rough 
laboratory,  and  there  I  was  able  to  work  in  the  evenings  or  during 
vacations.  In  this  laboratory  a  research  was  carried  on  conjointly 
with  Mr  Church  on  some  colouring  matters  derived  from  di- 
nitrobenzene  and  dinitronaphthalene.  One  of  the  products  we 
then  obtained  afterwards  proved  to  be  amidoazonaphthalene,  or, 
as  we  called  it,  azodinaphthyldiamine.  This  appears  to  have  been 
the  first  case  of  a  definite  compound  being  obtained  of  the  azo 
class  and  shown  to  possess  dyeing  powers.  As  Dr  Caro  has 
referred  to  this  in  his  notice  in  the  Berichte  of  the  late  Peter 
Griess,  I  need  not  make  any  further  observations  on  the  subject 
here  (Ber.,  1892,  25,  4,  ion). 

At  this  period  much  interest  was  taken  in  the  artificial  forma- 
tion of  natural  organic  substances  ;  but  at  the  time  I  was  at  the 
Royal  College  of  Chemistry,  although  the  theory  of  compound 
radicles,  the  doctrine  of  substitution,  etc.,  were  occupying  much 
attention,  very  little  was  known  of  the  internal  structure  of  com- 
pounds and  the  conception  as  to  the  method  by  which  one  com- 
pound might  be  formed  from  another  was  necessarily  very  crude. 

Thus,  in  the  Report  of  the  Royal  College  of  Chemistry, 
published  in  1849,  Hofmann  refers  to  the  artificial  formation  of 
quinine  as  a  great  desideratum,  and  then  states  : — 

"It  is  a  remarkable  fact  that  naphthalene,  the  beautiful  hydro- 
carbon of  which  immense  quantities  are  annually  produced  in  the 
manufacture  of  coal  gas,  when  subjected  to  a  series  of  chemical 
processes,  may  be  converted  into  a  crystalline  alkaloid.  This 


HOFMANN   MEMORIAL   LECTURE  149 

substance,  which  has  received  the  name  of  naphthalidine,  contains 
20  equivalents  of  carbon,  9  equivalents  of  hydrogen,  and  i 
equivalent  of  nitrogen."  (C  =  6.  O  =  8.) 

"  Now  if  we  take  20  equivalents  of  carbon,  1 1  equivalents  of 
hydrogen,  i  equivalent  of  nitrogen,  and  2  equivalents  of  oxygen, 
as  the  composition  of  quinine,  it  will  be  obvious  that  naphtha- 
lidine,  differing  only  by  the  elements  of  2  equivalents  of  water, 
might  pass  into  the  former  alkaloid  simply  by  an  assumption  of 
water.  We  cannot,  of  course,  expect  to  induce  the  water  to 
enter  merely  by  placing  it  in  contact,  but  a  happy  experiment 
may  attain  this  end  by  the  discovery  of  an  appropriate  meta- 
morphic  process." 

In  fact  there  was  but  little  other  ground  to  work  upon  in 
many  instances  than  this  kind  of  speculation. 

As  a  young  chemist  I  was  ambitious  enough  to  wish  to  work 
on  this  subject  of  the  artificial  formation  of  natural  organic  com- 
pounds. Probably  from  reading  the  above  remarks  on  the 
importance  of  forming  quinine,  I  began  to  think  how  it  might 
be  accomplished,  and  was  led  by  the  then  popular  additive  and 
subtractive  method  to  the  idea  that  it  might  be  formed  from 
toluidine  by  first  adding  to  its  composition  CJfri^  by  substituting 
allyl  for  hydrogen,  thus  forming  allyltoluidine,  and  then  removing 
2  hydrogen  atoms  and  adding  2  atoms  of  oxygen,  thus 

2(C10H18N)  +  30  =  C20H24N202  +  H20 

Allyltoluidine.  Quinine. 

The  allyltoluidine  having  been  prepared  by  the  action  of 
allyl  iodide  on  toluidine,  was  converted  into  a  salt  and  treated 
with  potassium  dichromate  ;  no  quinine  was  formed,  but  only  a 
dirty  reddish-brown  precipitate.  Unpromising  though  this  result 
was,  I  was  interested  in  the  action,  and  thought  it  desirable  to 
treat  a  more  simple  base  in  the  same  manner.  Aniline  was 
selected,  and  its  sulphate  was  treated  with  potassium  dichromate  ; 
in  this  instance  a  black  precipitate  was  obtained,  and,  on  exami- 
nation, this  precipitate  was  found  to  contain  the  colouring  matter 
since  so  well  known  as  aniline  purple  or  mauve,  and  by  a  number 
of  other  names.  All  these  experiments  were  made  during  the 
Easter  vacation  of  1856  in  my  rough  laboratory  at  home.  Very 
soon  after  the  discovery  of  this  colouring  matter,  I  found  that  it 
had  the  properties  of  a  dye,  and  that  it  resisted  the  action  of  light 
remarkably  well. 


150         THE   BRITISH   COAL-TAR   INDUSTRY 

After  the  vacation,  experiments  were  continued  in  the  even- 
ings when  I  had  returned  from  the  Royal  College  of  Chemistry, 
and  combustions  were  made  of  the  colouring  matter.  I  showed 
it  to  my  friend  Church,  with  whom  I  had  been  working,  on  his 
visiting  my  laboratory,  and  who,  from  his  artistic  tastes,  had  a 
great  interest  in  colouring  matters,  and  he  thought  it  might  be 
valuable  and  encouraged  me  to  continue  to  work  upon  it ;  but 
its  evident  costliness  and  the  difficulties  of  preparing  aniline  on 
the  large  scale,  made  the  probability  of  its  proving  of  practical 
value  appear  very  doubtful.  Through  a  friend,  I  then  got  an 
introduction  to  Messrs  Pullar,  of  Perth,  and  sent  them  some 
specimens  of  dyed  silk.  On  I2th  June  1856,  I  received  the 
following  reply  : — 

c<  If  your  discovery  does  not  make  the  goods  too  expensive, 
it  is  decidedly  one  of  the  most  valuable  that  has  come  out  for  a 
very  long  time.  This  colour  is  one  which  has  been  very  much 
wanted  in  all  classes  of  goods,  and  could  not  be  obtained  fast  on 
silks,  and  only  at  great  expense  on  cotton  yarns.  I  enclose  you 
pattern  of  the  best  lilac  we  have  on  cotton — it  is  dyed  only  by  one 
house  in  the  United  Kingdom,  but  even  this  is  not  quite  fast, 
and  does  not  stand  the  tests  that  yours  does,  and  fades  by 
exposure  to  air.  On  silk  the  colour  has  always  been  fugitive  : 
it  is  done  with  cudbear  or  archil,  and  then  blued  to  shade." 

This  somewhat  lengthy  extract  is  quoted  because  it  gives  a 
glimpse  at  the  state  of  the  dyeing  trade  in  reference  to  this  shade 
of  colour  at  that  period. 

This  first  report  was  very  satisfactory  ;  the  "  if  "  with  which 
it  commenced  was,  however,  a  doubtful  point. 

During  the  summer  vacation,  however,  the  preparation  of  the 
colouring  matter  on  a  very  small,  technical  scale  was  undertaken, 
my  brother  (the  late  T.  D.  Perkin)  assisting  me  in  the  operations, 
and,  after  preparing  a  few  ounces  of  product,  the  results  were 
thought  sufficiently  promising  to  make  it  desirable  to  patent  the 
process  for  the  preparation  of  this  colouring  matter.  This  was 
done  on  26th  August  1856  (Patent  No.  1984).  A  visit  was  then 
made  to  Messrs  Pullar's,  and  experiments  on  cotton  dyeing  were 
made,  but,  as  no  suitable  mordants  were  known  for  this  colouring 
matter,  only  the  pale  shades  of  colour,  produced  by  the  natural 
affinity  of  the  dye  for  the  vegetable  fibre,  were  obtained  ;  these, 
however,  were  admired.  Experiments  on  calico  printing  were 
also  made  at  some  print  works,  but  fears  were  entertained  that  it 


HOFMANN   MEMORIAL  LECTURE  151 

would  be  too  dear,  and,  although  it  proved  to  be  one  of  the  most 
serviceable  colours  as  regards  fastness,  yet  the  printers  were  not 
satisfied  with  it  because  it  would  not  resist  the  action  of  chloride 
of  lime  like  madder  purple. 

Although  the  results  were  not  so  encouraging  as  could  be 
wished,  I  was  persuaded  of  the  importance  of  the  colouring 
matter,  and  the  result  was  that,  in  October,  I  sought  an  interview 
with  my  old  master,  Hofmann,  and  told  him  of  the  discovery 
of  this  dye,  showing  him  patterns  dyed  with  it,  at  the  same  time 
saying  that  as  I  was  going  to  undertake  its  manufacture,  I  was 
sorry  that  I  should  have  to  leave  the  Royal  College  of  Chemistry. 
At  this  he  appeared  much  annoyed,  and  spoke  in  a  very  dis- 
couraging manner,  making  me  feel  that  perhaps  I  might  be  taking 
a  false  step  which  might  ruin  my  future  prospects.  I  have  some- 
times thought  that,  appreciating  the  difficulties  of  producing  such 
compounds  as  aniline  and  this  colouring  matter  on  the  large  scale, 
Hofmann  perhaps  anticipated  that  the  undertaking  would  be  a 
failure,  and  was  sorry  to  think  that  I  should  be  so  foolish  as  to 
leave  my  scientific  work  for  such  an  object,  especially  as  I  was 
then  but  a  lad  of  eighteen  years  of  age  ;  and  I  must  confess  that 
one  of  my  great  fears  on  entering  into  technical  work  was  that  it 
might  prevent  my  continuing  research  work,  but  I  determined 
that,  as  far  as  possible,  this  should  not  be  the  case. 

Still,  having  faith  in  the  results  I  had  obtained,  I  left  the 
College  of  Chemistry  and  continued  my  experiments,  and  found 
that  not  only  aniline,  but  also  toluidine,  xylidine,  and  cumidine 
gave  a  purple  colouring  matter  when  oxidised. 

The  following  is  a  copy  of  the  principal  part  of  the  complete 
specification  of  the  patent  I  took  out  at  this  time  : — 

DYEING  FABRICS 

"  The  nature  of  my  invention  consists  in  producing  a  new 
colouring  matter  for  dyeing  with  a  lilac  or  purple  colour  stuffs 
of  silk,  cotton,  wool,  and  other  materials  in  the  manner 
following  : — 

"  I  take  a  cold  solution  of  sulphate  of  aniline,  or  a  cold 
solution  of  sulphate  of  toluidine,  or  a  cold  solution  of  sulphate 
of  xylidine,  or  a  cold  solution  of  sulphate  of  cumidine,  or  a 
mixture  of  any  one  of  such  solutions  with  any  others  or  other  of 
them,  and  as  much  of  a  cold  solution  of  a  soluble  bichromate  as 


152         THE   BRITISH   COAL-TAR   INDUSTRY 

contains  base  enough  to  convert  the  sulphuric  acid  in  any  of  the 
above-mentioned  solutions  into  a  neutral  sulphate.  I  then  mix 
the  solutions  and  allow  them  to  stand  for  10  or  12  hours, 
when  the  mixture  will  consist  of  a  black  powder  and  a  solution 
of  a  neutral  sulphate.  I  then  throw  this  mixture  upon  a  fine 
filter,  and  wash  it  with  water  till  free  from  the  neutral  sulphate. 
I  then  dry  the  substance  thus  obtained  at  a  temperature  of  100° 
C.,  or  212°  F.,  and  digest  it  repeatedly  with  coal-tar  naphtha, 
until  it  is  free  from  a  brown  substance  which  is  extracted  by  the 
naphtha.  Any  other  substance  than  coal-tar  naphtha  may  be 
used  in  which  the  brown  substance  is  soluble  and  the  colouring 
matter  is  not  soluble.  I  then  free  the  residue  from  the  naphtha 
by  evaporation,  and  digest  it  with  methylated  spirit,  or  any  other 
liquid  in  which  the  colouring  matter  is  soluble,  which  dissolves 
out  the  new  colouring  matter.  I  then  separate  the  methylated 
spirit  from  the  colouring  matter  by  distillation,  at  a  temperature 
of  ioo°C.  or  2 1 2°  F." 

Fresh  quantities  of  colouring  matter  were  prepared  and  taken 
to  Scotland,  and,  although  the  method  of  applying  it  by  means 
of  lacterin  (casein)  was  then  found  to  give  very  good  results, 
yet  the  printers  who  tried  it  did  not  show  any  great  enthusiasm  ; 
and  even  Messrs  Pullar  began  to  fluctuate  in  their  opinion  as  to 
the  advisability  of  erecting  plant  for  its  manufacture,  and  wrote  : 
— "  Should  it  appear  that  it  will  not  be  of  service  to  printers, 
it  will  be  questionable  whether  it  would  be  wise  to  erect  works 
for  the  quantity  dyers  alone  will  require."  In  January  1867, 
Mr  R.  Pullar,  however,  advised  me  to  see  Mr  Thos.  Keith,  a 
silk  dyer  of  Bethnal  Green,  London,  and,  after  making  a  few  ex- 
periments with  the  colouring  matter,  and  exposing  the  specimens 
he  dyed  to  the  light  for  some  time,  he  was  much  pleased  with  the 
result,  and  encouraged  me  to  go  on  with  its  production. 

I  was  then  joined  in  the  undertaking  by  my  father — who 
was  a  builder,  and  had  sufficient  faith  in  the  project  to  risk  the 
necessary  capital — and  also  by  my  brother,  who  also  had  a  good 
knowledge  of  building,  and,  as  he  had  taken  part  in  the  pre- 
liminary experiments  on  the  preparation  of  the  dye,  his  assistance 
proved  most  valuable,  especially  as  he  was  possessed  of  good 
business  capabilities.  Plans  were  prepared  and  a  site  obtained  at 
Greenford  Green,  near  Harrow,  and  in  June  1857  the  building 
of  the  works  was  commenced. 


HOFMANN   MEMORIAL   LECTURE  153 

At  this  time,  neither  I  nor  my  friends  had  seen  the  inside  of 
a  chemical  works,  and  whatever  knowledge  I  had  was  obtained 
from  books.  This,  however,  was  not  so  serious  a  drawback  as 
at  first  it  might  appear  to  be,  as  the  kind  of  apparatus  required 
and  the  character  of  the  operations  to  be  performed  were  so 
entirely  different  from  any  in  use  that  there  was  but  little  to 
copy  from. 

In  commencing  this  manufacture,  it  was  absolutely  necessary 
to  proceed  tentatively,  as  most  of  the  operations  required  new 
kinds  of  apparatus  to  be  devised  and  tried  before  more  could  be 
ordered  to  carry  out  the  work  on  any  scale. 

But  the  mechanical  were  not  the  only  difficulties.  Benzene 
at  this  time  was  only  made  to  a  very  limited  extent,  as  there  was 
but  little  use  for  it,  and  it  was  only  after  making  several  inquiries 
that  it  was  ascertained  where  it  could  be  obtained.  That  used  at 
first  came  from  Messrs  Miller  &  Co.,  of  Glasgow.  It  was  also 
of  very  unequal  quality,  and  required  refractionating  before  use  ; 
its  price  was  55.  per  gallon.  No  nitric  acid  sufficiently  strong  for 
the  preparation  of  nitrobenzene  could  be  obtained  commercially, 
and,  as  we  did  not  want  to  complicate  our  works  by  manu- 
facturing the  substance,  experiments  were  made  with  a  mixture 
of  sodium  nitrate  and  sulphuric  acid,  using  the  latter  in  rather 
larger  proportions  than  necessary  to  give  an  acid  sodium  sulphate. 
This  method  was  found  to  succeed  on  the  small  scale,  but,  when 
working  with  large  quantities,  special  apparatus  had  to  be  devised, 
and  a  great  many  precautions  had  to  be  taken  to  regulate  the 
operation  ;  however,  very  large  quantities  of  nitrobenzene  were 
made  by  it.  Nitrobenzene  had  never  been  prepared  in  iron 
vessels  before  this  time. 

It  was  only  three  years  before  the  works  were  started  that 
B£champ  had  made  the  interesting  discovery  that  finely  divided 
iron  and  acetic  acid  were  capable  of  converting  nitrobenzene  into 
aniline  ;  had  it  not  been  for  this  discovery,  the  coal-tar  colour 
industry  could  not  have  been  started.  To  carry  this  process  out 
on  the  large  scale,  special  apparatus  was  also  required,  and,  on 
account  of  the  energy  of  the  action  which  takes  place,  special 
precautions  had  to  be  adopted  ;  but  no  great  difficulties  were 
encountered  in  this  operation.  Potassium  bichromate  at  that 
date  fluctuated  between  9fd.  and  nd.  per  lb.,  and  was  therefore 
a  costly  product. 

Many  more  details  might  be  gone  into  in  reference  to  the 


154         THE   BRITISH   COAL-TAR   INDUSTRY 

difficulties  to  be  contended  against  at  the  starting  of  the  industry, 
but  sufficient  has  been  said  to  give  some  idea  of  them  ;  however, 
in  less  than  six  months  after  the  building  of  the  works  was  com- 
menced, namely,  in  December  1857,  aniline  purple,  or  Tyrian 
purple,  as  it  at  first  was  called,  was  in  use  for  silk  dyeing  in  Mr 
Keith's  dye-house. 

But  in  dyeing  large  quantities  of  silk,  difficulties  were  again 
encountered,  on  account  of  the  great  affinity  of  the  colouring 
matter  for  the  fibre  causing  unevenness,  and  some  time  was  taken 
up  in  experimenting  on  this  subject,  until  eventually  it  was  found 
that  by  dyeing  in  a  soap  bath  a  very  pure  and  even  colour  could 
be  produced.  This  process  was  afterwards  found  to  be  the  most 
suitable  for  dyeing  silk  with  magenta,  Hofmann's  violet,  and 
many  other  colouring  matters. 

Aniline  purple  having  now  been  proved  to  be  an  important 
colouring  matter,  which  could  be  produced  on  a  manufacturing 
scale,  it  attracted  much  attention,  and,  as  a  consequence,  many 
others  commenced  its  manufacture,  and  began  to  experiment  with 
aniline,  especially  in  France  ;  all  kinds  of  oxidising  agents  were 
used,  but  potassium  dichromate  still  proved  to  be  the  best,  the 
next  best  being  chloride  of  copper,  the  use  of  which  was  patented 
by  Dale  and  Caro,  in  1860. 

The  French  manufacturers  were  not  long  before  they  succeeded 
in  producing  the  colouring  matter  (the  French  patent  being 
invalid,  owing  to  a  mistake  as  to  the  date  it  was  necessary  to 
take  it  out  in  reference  to  that  of  the  English  patent),  and  in 
using  it  in  dyeing  their  goods,  both  silk  and  cotton.  The 
calico  printers  of  this  country  then  began  to  be  alive  to  the 
necessity  of  following  them,  and  this  made  the  demand  for  the 
aniline  purple — which  the  French  now  began  to  call  mauve — so 
great  that,  notwithstanding  the  continued  increase  which  had  been 
taking  place  in  the  works  at  Greenford  Green,  it  could  not  be 
kept  pace  with.  At  this  time,  a  very  beautiful  archil  colour  had 
been  produced  by  Messrs  Guinon,  Marnas,  &  Bonnet,  called 
French  purple  ;  this  also  was  applied  to  calico  printing,  and  the 
printers  in  this  country  who  could  not  get  a  supply  of  aniline 
purple  used  this  until  their  requirements  could  be  met.  A  little 
before  this,  Mr  Pullar  and  I  separately  discovered  a  process  for 
mordanting  cotton,  so  that  it  could  be  dyed  with  aniline  purple  to 
any  depth  of  colour,  and  thus  it  became  of  much  more  value  to 
the  cotton  dyer  than  it  was  so  long  as  its  natural  affinity  for  the 


HOFMANN    MEMORIAL   LECTURE  155 

fibre  could  alone  be  relied  upon.  The  process  consisted  in  the 
use  of  tannin  and  a  metallic  oxide. 

For  calico  printing,  the  colouring  matter  was  first  applied  in 
combination  with  lacterin,  albumin,  or  gluten,  but  endeavours 
were  soon  made  to  find  some  new  method  by  which  these  might 
be  dispensed  with,  and  I  worked  for  some  considerable  time 
on  this  subject  at  the  Dalmonach  Print  Works,  Alexandria, 
Dumbartonshire,  where  the  colour  was  first  practically  used  for 
printing  in  this  country.  I  devised  a  process,  which  consisted  in 
printing  on  a  lead  salt,  converting  this  into  a  salt  containing  a 
fatty  acid  by  means  of  soap,  and  then  dyeing  in  a  soap  bath  con- 
taining the  colouring  matter  ;  the  fatty  lead  salt  then  took  up  the 
colouring  matter,  whilst  the  soap  prevented  the  white  from  being 
stained  ;  this  process  was  patented  by  myself  and  Mr  Mathew 
Grey.  It  produced  beautiful  shades  of  colour,  but  could  not  be 
used  where  combinations  with  other  colours  were  required,  and 
therefore  did  not  prove  useful. 

Printers  then  experimented  on  the  use  of  tannin  and  a 
metallic  oxide,  the  process  used  in  cotton  dyeing  devised  by 
Mr  Pullar  and  myself  ;  a  modified  form  of  this  process  has 
become  the  most  important  used.  Another  process  was  also 
very  largely  used,  patented  by  M.  Schultz  and  myself,  which 
consisted  in  forming  an  insoluble  arsenite  of  alumina  and  colour- 
ing matter  on  the  fibre,  the  colours  produced  in  this  way  being 
very  brilliant,  as  well  as  fast  to  washing.  Before  the  aniline 
purple  could  be  introduced  for  dyeing  woollen  and  mixed  fabrics, 
some  weeks  were  also  spent  at  Bradford  in  finding  out  suitable 
methods  of  applying  it. 

Thus  it  will  be  seen  that,  in  the  case  of  this  new  colouring 
matter,  not  only  had  the  difficulties  incident  to  its  manufacture 
to  be  grappled  with,  and  the  prejudices  of  the  consumer  over- 
come, but,  owing  to  the  fact  that  it  belonged  to  a  new  class  of 
dyestuffs,  a  large  amount  of  time  had  to  be  devoted  to  the  study 
of  its  applications  to  dyeing,  calico  printing,  etc.  It  was,  in  fact, 
all  pioneering  work — clearing  the  road,  as  it  were,  for  the  intro- 
duction of  all  the  colouring  matters  which  followed,  all  the  pro- 
cesses worked  out  for  dyeing  silk,  cotton,  and  wool,  and  also  for 
calico  printing,  afterwards  proving  suitable  for  magenta,  Hofmann 
violet,  etc. 

All  this  time  a  host  of  experimentalists  continued  making 
trials  with  aniline  and  all  kinds  of  chemicals,  and  early  in  1859, 


156         THE   BRITISH   COAL-TAR   INDUSTRY 

three  years  after  the  discovery  of  aniline  purple,  or  mauve, 
M.  Verguin  discovered  fuchsine,  also  called  magenta  and  roseine, 
and,  later  on,  rosaniline  by  Hofmann. 

From  what  has  been  said  above,  it  will  be  seen  that  the  dis- 
covery of  this  colouring  matter  was  made  under  more  favourable 
auspices  than  that  of  mauve  :  everything  was  ready  for  its  pro- 
duction and  application,  it  was  also  an  easier  product  to  manu- 
facture and  relatively  to  the  aniline  used  was  formed  in  much 
larger  quantities  than  mauve  was,  but  it  was  not  nearly  so  fast 
against  light,  and  when  first  experimented  with  I  thought  this 
would  have  been  very  detrimental  to  its  extensive  use,  remember- 
ing the  experience  that  I  had  gone  through  with  mauve  ;  but 
things  had  changed,  and  the  love  of  brilliancy  had  begun  to 
outrun  the  regard  for  durability,  indeed,  as  is  well  known, 
magenta  has  proved  to  be  one  of  the  most  successful  of  the 
coal-tar  colours  ever  discovered.  M.  Verguin's  process  was  a 
very  remarkable  one,  and  it  has  never  transpired  whether  he 
was  led  to  it  by  any  scientific  reasoning  or  not ;  it  will  be 
remembered  that  it  consists  in  heating  commercial  aniline  and 
anhydrous  tetrachloride  of  tin  nearly  up  to  the  boiling-point  of 
the  mixture  ;  it  was  first  carried  out  by  Messrs  Reynard  Bros., 
of  Lyons. 

We  were  thus  indebted  to  France  for  the  second  step  in  the 
coal-tar  colour  industry.  Soon  other  processes  were  invented  for 
the  production  of  magenta,  but  the  most  practical  one,  after 
M.  Verguin's,  was  that  in  which  mercury  nitrate  was  used  ;  large 
quantities  of  colouring  matter  were  made  by  this  method. 

The  fuchsine,  or  magenta,  first  made  in  France,  was  but  very 
imperfectly  purified,  and  a  good  deal  of  that  afterwards  made  in 
Germany  simply  consisted  of  the  "  melt "  produced  by  heating 
aniline  with  mercury  nitrate. 

Being  naturally  interested  in  this  new  colouring  matter,  I 
made  many  experiments  with  it,  and  in  a  lecture  I  delivered  before 
this  Society,  on  i6th  May  1861  (Jour.  Chem.  Soc.y  1862,  14, 
230)  (when  I  was  honoured  by  the  presence  of  Michael  Faraday), 
an  account  of  some  of  the  results  obtained  by  its  examination 
was  given,  in  which  it  was  shown  that  it  was  the  salt  of  an 
organic  base  (a  fact  at  that  time  believed  in  by  some,  but  doubted 
by  others)  precipitated  by  alkalis  and  at  the  same  time  dissolved 
by  them  to  some  extent,  yielding  colourless  solutions,  and  that 
its  nitrate  could  be  obtained  in  the  form  of  octahedra,  having 


HOFMANN    MEMORIAL  LECTURE  157 

a  beautiful  green  metallic  reflection  ;  this  was  the  first  occasion, 
I  believe,  on  which  it  was  described  as  a  crystalline  compound. 
Attention  was  also  called  to  the  fact  that  its  salts  could  not  con- 
tain oxygen,  which  was  afterwards  confirmed  by  Hofmann  ;  and 
it  was  further  pointed  out  that  other  products  were  formed  along 
with  it,  one  possessing  an  orange  colour  (chrysaniline),  and  another 
a  purple  colour  (violaniline,  mauvaniline,  etc.). 

In  speaking  of  the  manufacture  of  rosaniline  in  this  country, 
I  must  first  refer  to  another  of  Hofmann's  pupils,  Edward 
Chambers  Nicholson,  of  the  firm  of  Simpson,  Maule  &  Nichol- 
son, who  brought  the  manufacture  of  this  compound  to  a  state 
of  perfection  which,  I  believe,  has  not  been  surpassed — so  far  as 
purity  is  concerned — up  to  the  present  time. 

It  is  of  interest  to  trace  the  manner  in  which  Messrs  Simpson, 
Maule  &  Nicholson  became  connected  with  the  coal-tar  colour 
industry.  They  were  originally  manufacturers  of  fine  chemicals, 
etc.  When  aniline  purple  was  found  to  be  successful,  and  was 
exciting  a  great  deal  of  interest,  this  and  other  firms  were  anxious 
to  manufacture  it,  and  consequently  wished  to  have  a  licence  for 
the  purpose,  but  no  agreement  could  be  come  to.  They  were 
then  very  desirous  of  manufacturing  nitrobenzene  for  our  use  in 
producing  aniline.  At  first  they  could  not  do  this  at  a  sufficiently 
low  price,  but  eventually  succeeded  in  producing  it  cheaply  enough 
to  make  it  worth  our  while  to  supplement  our  own  make  by 
theirs,  as  the  demand  for  aniline  purple  was  then  so  rapidly 
increasing.  In  this  way  they  soon  became  considerable  producers 
of  nitrobenzene  ;  they  then  set  to  work  to  prepare  aniline,  which 
after  a  time  they  succeeded  in  doing.  In  this  manner  they 
leisurely,  as  it  were,  became  fully  prepared  to  go  a  step  further, 
and  become  manufacturers  of  colouring  matters. 

Dr  David  Price  at  this  time  joined  the  firm,  and  Nicholson 
and  he  apparently  experimented  with  the  products  he  had  patented 
in  1859,  namely  violin,  purpurin,  and  roseine,  obtained  by  oxidis- 
ing aniline  with  lead  peroxide  ;  these  colouring  matters,  however, 
were  not  found  to  be  of  practical  value.  They  then  turned  their 
attention  to  the  newly  discovered  colouring  matter,  fuchsine. 
This  they  commenced  manufacturing,  giving  it  the  name  of  one 
of  Dr  Price's  products,  roseine. 

H.  Medlock,  another  of  Hofmann's  pupils  at  the  Royal 
College  of  Chemistry,  took  out  a  patent  on  i8th  January  1860, 
for  the  production  of  magenta,  by  heating  aniline  with  arsenic 


158         THE   BRITISH   COAL-TAR   INDUSTRY 

acid  ;  eight  days  later,  Nicholson  filed  a  similar  patent,  but  did 
not  proceed  with  it  when  he  learnt  what  Medlock  had  done. 
Medlock's  patent  is  notorious  for  the  amount  of  litigation  that 
arose  owing  to  the  occurrence  in  it  of  the  word  "  anhydrous." 
The  formation  of  magenta  by  the  use  of  arsenic  acid  proved  in 
the  hands  of  Nicholson,  and  also  of  others,  a  great  improvement 
on  the  previous  processes,  and  for  a  long  time  was  the  process 
for  the  production  of  this  colouring  matter,  until,  in  fact,  it  was 
superseded  by  the  use  of  nitrobenzene  instead  of  arsenic  acid. 

One  of  the  things  Hofmann  used  to  impress  on  those  of  his 
students  who  were  engaged  at  research  work  was  the  great 
importance  of  preparing  their  products  in  as  nearly  pure  a 
condition  as  possible — especially  those  which  were  to  be  submitted 
to  analysis  ;  some  of  us  used  to  think  that  we  should  get  as 
good  results  by  examining  the  substances  when  crystallised 
fewer  times  than  he  required,  especially  when  the  products  were 
difficult  to  obtain  and  the  quantities  became  smaller  and  smaller 
on  each  recrystallisation  ;  but  he  was  right.  Nicholson,  when  at 
the  Royal  College,  made  several  investigations  under  Hofmann's 
direction,  studying  the  compounds  of  phosphoric  acid  with 
aniline  ;  the  formation  of  cumidine  from  cumene  from  cuminic 
acid  ;  also  caffeine  and  some  of  its  compounds  ;  and,  in  con- 
junction with  F.  A.  Abel,  he  investigated  strychnine.  He  also 
appears  to  have  been  an  adept  at  combustions,  as  he  made  the 
combustion  of  benzene  for  Mansfield  ;  his  name  appearing  also 
in  de  la  Rue's  paper  on  cochineal  as  having  made  one  of  the 
combustions  of  nitrococcusic  acid.  There  is  no  doubt  that 
Hofmann's  teaching  as  to  the  importance  of  working  with  pure 
materials  was  strongly  impressed  upon  Nicholson  when  carrying 
on  these  researches,  and  that  it  greatly  influenced  him  when  he 
became  engaged  in  the  manufacture  of  colouring  matters.  It  is 
only  right  to  add  that  Dr  D.  Price,  with  whom  he  was  for  some 
time  associated  in  this  industry,  and  whom  I  knew  when  at  the 
Royal  College  of  Chemistry  as  a  most  thorough,  painstaking, 
and  careful  worker,  would  also  second  his  efforts  in  this  respect. 
I  may  also  add  that  I  feel  sure  Hofmann's  influence  in  this 
direction  had  also  a  considerable  influence  on  my  own  after- 
career  as  a  chemist. 

At  first  Messrs  Simpson,  Maule  &  Nicholson  supplied 
magenta,  or  roseine,  as  they  called  it,  to  the  dyers  in  alcoholic 
solution,  but  afterwards,  when  they  had  obtained  it  in  a  pure 


HOFMANN   MEMORIAL   LECTURE  159 

condition,  they  sold  it  in  crystals  (usually  the  oxalate).  In  their 
process  of  purification  they  boiled  the  crude  solution  of  the 
colouring  matter  with  milk  of  lime,  and  collected  the  base  which 
deposited  from  the  clear  solution  thus  obtained,  and  from  this 
prepared  the  desired  salts. 

By  this  time  the  coal-tar  colour  industry  had  become  one  of 
no  mean  dimensions  in  this  country,  and  also  in  France,  and 
it  was  quickly  developing  in  Germany  and  elsewhere.  The 
number  of  colours  was  also  increasing,  for  not  only  had  mauve 
or  aniline  purple  and  fuchsine  been  discovered,  but  Girard  and 
De  Laire  had  made  their  remarkable  discovery  of  imperial  violet 
and  blue  de  Lyon  by  heating  aniline  with  fuchsine,  thereby — as 
is  now  known — phenylating  this  colouring  matter. 

When  first  speaking  of  fuchsine,  I  mentioned  that  it  was 
discovered  by  M.  Verguin,  and,  from  a  practical  point  of  view, 
this  may  be  considered  correct.  Nevertheless  it  appears  to  have 
been  first  seen  as  far  back  as  1856,  when  Natanson  (Annalen  der 
Chemie  und  Pharmacie,  1856,98,  297)  observed  that  in  heating 
aniline  and  chloride  of  ethylene  in  a  sealed  tube  to  200°  C.,  the 
mixture  becomes  of  a  rich  blood-red  colour  ;  Hofmann  also, 
in  1858,  when  acting  on  aniline  with  carbon  tetrachloride,  ob- 
tained, besides  carbotriphenyltriamine,  a  small  quantity  of  this 
substance  as  a  secondary  product,  which  he  describes  as  "  a  very 
soluble  substance  of  a  magnificent  crimson  colour."  * 

In  the  Report  of  the  Exhibition  of  1862  (Class  II.,  sec.  A, 
p.  126),  Hofmann,  in  speaking  of  the  discovery  of  this  colouring 
matter,  says  : — "  It  may  be  said  to  have  been  discovered  at  two 
different  times  according  as  the  question  is  considered  from  a 
scientific  or  industrial  point  of  view  ; "  and  at  p.  126: — 
"  Industrially,  the  discovery  of  aniline  red  was  made  by  Messrs 
Verguin  and  Renard  Brothers  of  Lyons/* 

The  investigation  Hofmann  made  with  the  Nicholson  pro- 
ducts soon  set  at  rest  the  conflicting  views  which  at  first  existed 
in  reference  to  this  colouring  matter,  and  proved  that  it  was  a 

1  About  two  years  after  M.  Verguin's  discovery  of  fuchsine,  the  use  of 
carbon  tetrachloride  and  aniline  as  a  means  of  preparing  this  colouring 
matter  was  tried,  for  reasons  connected  with  patent  rights,  by  MM.  Monnet 
and  Drury  of  Lyons.  They  first  employed  a  temperature  of  ii6°-ii8°  C. 
until  the  reaction  between  these  two  substances  was  over,  and  then  heated 
the  product  up  to  170°  or  180°  C.  By  this  means  of  working,  they  apparently 
obtained  a  larger  yield  than  Hofmann,  but  the  process  never  became  a 
practical  one.  See  Moniteur  Scientifique,  t.  Hi.,  i5th  January  1861. 


160         THE   BRITISH   COAL-TAR   INDUSTRY 

well-defined  triamine — which  he  renamed  rosaniline — forming 
salts  free  from  oxygen.  He  then  regarded  the  base,  which  had 
the  formula  C2oH2iN3O,  as  a  hydrate  of  the  anhydrous  compound 
C2oH19N3.  Hofmann  examined  many  of  the  salts  of  rosaniline 
— those  with  one  molecule  of  acid,  the  ordinary  salts  used  in 
dyeing,  and  the  hydrochloride  with  3  mols.  of  acid.  He  also 
obtained  the  interesting  compound,  leucaniline,  by  treating 
rosaniline  with  reducing  agents,  a  compound  which  has  its 
representation  in  all  triphenylmethane  colouring  matters.  The 
investigation  is  a  memorable  one,  as  being  the  first  investigation 
which  gave  correct  information  respecting  the  formula  of  a 
coal-tar  colouring  matter. 

It  had  been  observed  by  manufacturers  that  some  varieties  of 
aniline  yield  much  more  rosaniline  than  others,  samples  boiling 
at  temperatures  much  higher  than  the  boiling-point  of  the  pure 
compound  being  found  particularly  adapted  for  the  production  of 
the  red  ;  and  it  appears  that  Nicholson  had  ascertained  that  pure 
aniline  was  incapable  of  yielding  rosaniline.  Hofmann  studied 
this  subject,  using  aniline  prepared  from  indigo  and  from  pure 
benzene,  and  his  experiments  confirmed  Nicholson's.  The  idea 
then  naturally  suggested  itself,  that  the  toluidine  contained  in 
commercial  aniline  might  be  the  source  of  the  colouring  matter. 
But,  on  making  experiments  with  toluidine  (orthotoluidine  was 
not  then  known)  it  was  found  that  this  base  also  was  incapable 
of  producing  the  dyestuff;  on  taking  a  mixture  of  aniline  and 
toluidine,  however,  it  was  at  once  produced  in  quantity,  showing 
that  both  bases  were  necessary  for  its  production  (Report, 
International  Exhibition,  1862,  Class  II.,  sec.  A,  p.  130). 

This  discovery  was  of  great  importance  and  interest,  and 
explained  most  of  the  facts  connected  with  the  use  of  anilines  of 
different  boiling-points.  In  the  case  of  mauveine,  this  discovery 
was  not  of  so  great  importance  as  in  the  case  of  rosaniline,  because 
pure  aniline  yields  a  purple  colouring  matter  (pseudomauveine), 
as  well  as  mixtures  of  aniline  and  toluidine. 

Mauve  had  also  been  obtained  in  a  pure  crystallised  condition, 
but  technically  this  was  not  found  of  much  advantage,  as  the 
colours  obtained  with  it  in  this  condition  were  only  slightly 
superior  to  those  obtained  with  the  less  expensive  precipitated 
colouring  matter  which  was  usually  supplied  to  the  consumer. 

Having  examined  aniline  red  or  rosaniline,  Hofmann  was  also 
desirous  of  investigating  aniline  purple  or  mauve,  but  when  he 


HOFMANN    MEMORIAL   LECTURE  161 

spoke  to  me  on  the  subject,  the  colouring  matter  was  already 
under  investigation  in  my  own  laboratory. 

The  crystallised  aniline  purple  sent  into  the  market  was  the 
acetate  of  the  base  to  which  I  gave  the  name  mauveine.  This 
base  is  remarkable  for  its  stability  and  tinctorial  power.  Its 
investigation  (Proc.  Roy.  Soc.,  1864,  12,  713)  showed  that  it 
possesses  the  formula  C27H24N4,  and  that,  unlike  rosaniline,  it  is 
not  a  hydroxy  compound.  Moreover,  the  base  is  a  strongly 
coloured  compound  of  a  blue-violet  colour.  When  treated  with 
reducing  agents,  it  yields  a  leuco  compound,  but  this  is  so 
sensitive  to  the  action  of  oxygen  that  on  exposure  to  the  air  it 
instantly  changes  back  to  mauveine.  Its  ordinary  salts  are  pro- 
duced from  i  mol.  of  base  and  i  mol.  of  acid.  From  a  more 
recent  research  on  this  colouring  matter  (Jour.  Chem.  Soc.,  1879, 
717),  I  have  shown  that  a  dihydrochloride  and  corresponding 
platinum  salt  can  be  obtained,  and  the  characteristic  changes 
which  a  solution  of  this  substance  in  concentrated  sulphuric  acid 
undergoes  on  dilution,  namely,  from  a  dull  green  to  a  blue,  and 
lastly  to  a  purple,  show  that  probably  salts  formed  by  the  union 
of  mauveine  with  more  than  2  mols.  of  acid  exist.  The  ordinary 
commercial  product  has  also  been  shown  to  consist  of  two 
colouring  matters,  one  forming  very  soluble  and  apparently  un- 
crystallisable  salts  called  pseudomauveine,  having  the  formula 
C24H2oN4,  and  produced  from  pure  aniline  ;  the  other  forming 
less  soluble  and  beautifully  crystalline  salts  of  the  formula 
C27H24N4,  derived  from  paratoluidine  and  aniline.  This  colour- 
ing matter,  unlike  rosaniline,  does  not  freely  undergo  changes 
with  reagents  on  account  of  its  great  stability,  so  that  few 
derivatives  have  been  obtained  from  it  serving  to  elucidate  its 
constitution,  which  is  still  unknown. 

Messrs  Simpson,  Maule  &  Nicholson,  after  engaging  in  the 
manufacture  of  rosaniline  for  some  time,  undertook  that  of  Girard 
and  De  Laire's  imperial  violet  and  bleu  de  Lyon,  obtained  by 
heating  a  salt  of  rosaniline  with  aniline  (Pat.,  January  1861). 

Mr  Nicholson  spent  much  time  in  studying  the  conditions 
most  favourable  to  the  production  of  these  compounds,  especially 
the  blue,  so  as  to  obtain  it  in  a  pure  condition,  and  in  this  he 
was  very  successful.  This  was  due  to  his  knowledge  of  the 
importance  of  using  pure  materials  in  its  manufacture.  The 
rosaniline  base  he  used  was  not  merely  the  best  he  produced  for 
the  preparation  of  rosaniline  salts,  but  he  purified  it  much  further 

ii 


1 62         THE   BRITISH   COAL-TAR   INDUSTRY 

by  means  of  methylated  spirit  ;  the  aniline  was  prepared  for  the 
purpose  from  the  purest  benzene  he  could  obtain  ;  he  also  paid 
much  attention  to  the  selection  of  the  best  acid  to  use  in  com- 
bination with  rosaniline,  and  found  that  weak  organic  acids,  such 
as  acetic  and  benzoic  acids,  were  the  most  suitable.  In  this  way 
he  eventually  obtained  the  blue  in  a  condition  of  purification 
unequalled  by  others. 

Provided  with  the  purified  blue  by  Nicholson,  Hofmann  soon 
discovered  that  the  base  had  the  formula  C38H33N3O  ;  this  he 
regarded  as  a  hydrate  of  the  compound  C38H31N3,  of  which  he 
obtained  a  hydrochloride  of  the  composition  C38H31N3HC1.  The 
blue  was  converted  by  reducing  agents  into  a  leuco  compound. 

As  far  back  as  1850  (Phil.  Trans.,  1,  93,  Jour.  Chem.  Soc.,  3, 
283),  when  engaged  in  his  researches  on  the  molecular  constitution 
of  the  volatile  organic  bases,  Hofmann  had  endeavoured  to  displace 
the  hydrogen  in  aniline  by  phenyl,  by  heating  it  with  phenol, 
but  was  unsuccessful ;  we  can,  therefore,  easily  understand  his 
delight  when  he  found  that  on  boiling  rosaniline  with  aniline  the 
colouring  matter  became  phenylated.  The  long-desired  method 
of  effecting  the  displacement  of  hydrogen  by  phenyl  had,  in  fact, 
been  discovered,  and  we  find  that  no  sooner  had  he  recognised  that 
the  blue  was  a  triphenylrosaniline  than  he  telegraphed  the  result 
to  Paris.1  The  Comptes  rendus  of  the  sitting  of  the  Academy 
of  1 8th  May  1863  contains  the  following  note  : — 

"  M.  Le  Secretaire  Perpetuel  communique  une  Courte  Note 
de  M.  Hofmann  con£ue  dans  les  termes  suivants. 

"  Bleu  d'Aniline. — En  poursuivant  mes  recherches  sur  les 
couleurs  d'aniline,  je  suis  arrive  a  un  resultat  tres  simple  ;  le 
bleu  d'aniline  est  la  rosaniline  triphenylique  :  une  molecule  de 
rosaniline  et  trois  molecules  d'aniline  renferment  les  elements 
d'une  molecule  de  bleu  d'aniline  et  trois  molecules  d'ammoniaque." 
The  paper,  communicating  fuller  details  of  his  results  on  this 
colouring  matter,  was  read  on  6th  July  of  the  same  year  (Compt. 
rend.)  1863,  57,  25).  Speaking  in  this  paper  of  Nicholson,  he 
pays  him  this  tribute  :  "  That  in  him  was  united  the  genius  of 
the  manufacturer  and  the  habits  of  a  scientific  investigator." 

1  Hofmann  had  made  the  discovery  apparently  on  the  same  day,  for 
Professor  McLeod,  who  was  his  assistant  at  that  time,  gives  me  an  entry 
from  his  diary  dated  i8th  May  1863,  which  runs  thus:  "The  doctor  told  me 
that  he  had  made  a  fine  discovery,  and  that  aniline  blue  is  the  triphenylated 
rosaniline.  Rosaniline,  C20H19N3H2O ;  aniline  blue,  C20H16(C6H5)5N3H2O." 


HOFMANN    MEMORIAL   LECTURE  163 

We  find  the  discovery  of  the  phenylation  of  rosaniline  after- 
wards bearing  fresh  fruit  in  the  hands  of  De  Laire,  Girard,  and 
Chapoteaut,  who  established  the  remarkable  fact  that  when  boiled 
with  its  own  hydrochloride,  aniline  acted  in  a  similar  manner, 
producing  diphenylamine  and  ammonia  ;  by  using  aniline 
hydrochloride  and  toluidine,  they,  in  like  manner,  obtained 
phenyltoluylamine  (Compt.  rend.)  1866,  63,  91). 

Aniline  blue  having  proved  to  be  triphenylrosaniline,  it  was 
soon  seen  that  the  different  shades  of  violet  imperial  were 
rosanilines  more  or  less  phenylated. 

Nicholson  also  found  that,  on  heating  acetate  of  rosaniline  to 
200°— 215°  C.,  ammonia  was  disengaged,  and  a  purple  colouring 
matter  produced,  which  he  called  regina  purple.  This  substance 
was  found  to  be  a  monophenylrosaniline  (patented  2oth  January 
1862). 

One  of  the  great  obstacles  in  the  way  of  the  application  of 
aniline  blue  was  its  slight  solubility  in  water,  which  rendered  the 
dyeing  operations  unsatisfactory  ;  this  also  militated  against  its 
use  in  calico  printing  for  some  time  (the  most  suitable  process 
for  its  use  for  this  purpose  first  found  being  that  of  Schultz  and 
myself  with  arsenate  of  alumina,  but  with  this  long  steaming  and 
afterwards  clearing  in  a  soap  bath  was  required  ;  the  colours  thus 
obtained,  however,  were  very  pure  and  very  durable).  Nicholson 
naturally  was  very  desirous  of  overcoming  this  obstacle,  and  no 
doubt  the  well-known  process  of  rendering  indigo  soluble  by 
dissolving  it  in  sulphuric  acid,  and  thus  converting  it  into  a 
sulphonic  acid,  occurred  to  him  ;  at  any  rate,  by  experimenting 
in  this  direction,  he  succeeded  in  obtaining  the  desired  result  and 
patented  the  process  (ist  June  1862).  Nicholson  obtained  two 
sulphonic  acids — a  mono  and  a  tri — the  first  being  known  as 
Nicholson's  blue,  and  the  latter  as  soluble  blue,  and  it  is  owing 
to  the  discovery  of  these  derivatives  of  aniline  blue  or  triphenyl- 
rosaniline that  this  colouring  matter  became  of  such  importance. 

This  method  of  treating  aniline  blue  was  very  interesting  as 
being  the  first  instance  of  sulphonating  an  aniline  colour,  a 
process  which  of  late  years  has  become  of  so  much  importance, 
not  only  in  rendering  difficultly  soluble  dyes  soluble,  but 
also  in  changing  the  chemical  nature  of  the  colouring  matters, 
and  thus  extending  their  applications  as  dyes,  as  in  the  case  of 
rosaniline  sulphonic  acid. 

It  was  Nicholson  who  succeeded  in  isolating  the  yellow  qr 


164         THE   BRITISH   COAL-TAR   INDUSTRY 

orange  colouring  matter  which  is  formed  in  the  manufacture 
of  rosaniline  ;  he  prepared  it  in  a  pure  state,  and  called  it 
phosphine.  Hofmann  undertook  the  examination  of  this  dye, 
and  showed  that  it  is  represented  by  the  formula  C2oH17N3, 
differing  from  that  of  rosaniline  in  containing  2  atoms  of 
hydrogen  less  ;  the  base  is  capable  of  forming  salts  with  i  or  2 
molecules  of  hydrochloric  acid,  the  nitrate  being  remarkable  for 
its  insolubility. 

After  discovering  that  aniline  blue  or  bleu  de  Lyon  was  a 
triphenylrosaniline,  Hofmann  was  very  naturally  inclined  to 
experiment  on  rosaniline  with  the  agents  he  had  used  so  success- 
fully in  his  experiments  on  the  molecular  constitution  of  the 
volatile  organic  bases,  namely,  the  haloid  compounds  of  the 
alcohol  radicles,  to  see  what  influence  these  radicles  would  have 
if  introduced  into  the  base  :  he  found  that  they  had,  like  phenyl, 
though  not  to  the  same  extent,  a  blueing  effect,  the  colour 
changing  from  red  to  purple,  and  then  to  violet  as  the  hydrogen 
atoms  were  gradually  displaced,  colouring  matters  being  produced 
which  were  found  to  be  of  great  beauty  when  applied  to  silk,  etc. 
In  his  first  paper  on  these  products  (Compt.  rend.)  1863,  57,  30), 
he  gives  an  account  of  the  action  of  methyl,  ethyl,  and  amyl 
iodides  on  rosaniline,  and  amongst  the  products  he  obtained  at 
that  time  describes  the  highest  ethylated  derivative  he  had 
succeeded  in  producing  as  the  iodethylate  of  triethylrosamline, 
C2oHi6(C2H5)3N3 .  C2H5I. 

He  patented  the  method  of  producing  these  colouring  matters 
on  22nd  May  1863. 

It  is  easy  to  see  how  Hofmann  was  led  to  the  production  of 
these  compounds  in  the  regular  sequence  of  his  work,  but  it  is 
curious  that  E.  Kopp  had  evidently  prepared  some  of  them  as 
long  back  as  1861.  E.  Kopp  remarks  in  his  paper  in  the 
Comptes  rendus,  1861,  52,  363,  "  I  have  only  stated  in  my  notice 
these  substitutions  as  a  hypothesis,  but  their  existence  is  very 
real  ;  I  have  already  obtained  some  of  them,  and  it  is  a 
remarkable  thing  that  the  red  shade  disappears,  and  is  converted 
into  a  violet,  becoming  bluer  and  bluer  as  the  hydrogen  is  dis- 
placed by  the  hydrocarbons."  It  appears  that  he  sent  some 
specimens  of  his  products  to  M.  Dumas. 

When  Hofmann  patented  the  use  of  methyl,  ethyl,  and  amyl 
iodides  for  the  preparation  of  these  colouring  matters,  it  seemed 
almost  incredible  that  substances  such  as  these,  which  had 


HOFMANN    MEMORIAL   LECTURE  165 

hitherto  only  been  used  in  research,  should  be  employed  in  the 
manufacture  of  a  dye  ;  but  such  circumstances  have  constantly 
arisen  in  the  history  of  this  remarkable  industry — aniline  itself, 
the  parent  of  artificial  colours,  being  an  example — and  nothing 
now  appears  to  be  too  rare  or  difficult  to  prepare,  to  be  used  in 
its  development. 

It  is  difficult  to  understand  why  E.  Kopp  did  not  go  on  with 
his  work  on  these  substitution  compounds,  unless  it  was  owing 
to  the  fact  that  rosaniline  was  expensive  in  his  days,  and  he 
considered  the  alcoholic  haloids  too  costly  to  employ  for  practical 
purposes. 

The  Hofmann  violets  were  the  most  brilliant  in  colour  of  any 
which  had  been  produced,  and  proved  not  to  be  so  costly  as 
might  be  anticipated,  as  the  iodine  from  the  ethyl  iodide  used 
could  be  mostly  recovered  ;  but  these  colouring  matters  have 
not  the  stability  of  mauve  or  imperial  violet,  and  at  first  it  was 
thought  that  their  use  would  be  limited,  but  the  increasing 
desire  for  brilliancy  was  still  superseding  that  for  stability,  and 
the  result  was,  that  these  colouring  matters  were  very  largely 
used,  and  interfered  very  considerably  with  the  sale  of  the 
mauve  and  imperial  violets,  except  for  pale  shades  of  colour, 
when,  unless  the  colouring  matter  used  be  stable,  the  goods  fade 
so  quickly  as  to  be  of  little  value. 

The  products  formed  on  heating  mauveine  salts  with  aniline 
apparently  are  not  comparable  with  those  obtained  from  ros- 
aniline, and  although  the  product  becomes  bluer  no  ammonia  is 
evolved  ;  from  my  later  experiments,  it  seems  most  likely  that 
the  aniline  used  takes  no  part  in  the  change,  the  blueing  being 
a  change  in  the  colouring  matter,  the  consequence  of  the 
temperature  employed. 

When  treated  with  ethyl  iodide,  mauveine  behaves  unlike 
rosaniline,  yielding  a  beautiful  colouring  matter,  which  is  of  a 
redder  shade,  and  not  bluer  as  in  the  latter  case.  This  colouring 
matter,  called  dahlia  (patented  on  6th  November  1863),  consists 
of  a  monethylic  derivative  of  mauveine,  its  hydrochloride  being 
represented  by  the  formula  C27H23(C2H5)N4HC1.  No  further 
change  is  effected  by  ethyl  iodide,  and  it  is  uncertain  whether 
the  product  is  a  substitution  or  an  addition  compound  (it  may 
be  remarked  here  that  at  times  some  quantity  of  a  dark,  blue- 
black,  almost  insoluble  substance  containing  iodine  is  also 
produced). 


1 66         THE   BRITISH   COAL-TAR   INDUSTRY 

This  dahlia  or  ethylmauveine  was  used  by  the  calico  printers 
and  dyers  to  some  extent,  though  not  largely,  on  account  of  its 
costliness.  It  is,  however,  a  colouring  matter  which  gives 
shades  of  very  considerable  stability  on  exposure  to  light. 

The  discovery  that  the  introduction  of  such  radicles  as  phenyl 
or  ethyl  altered  the  colour  of  rosaniline  so  greatly,  made  it  of 
interest  to  see  whether  other  kinds  of  hydrocarbon  groups  could 
be  introduced  to  modify  its  tint.  Amongst  other  products, 
brominated  turpentine  was  used,  and  on  heating  it  with  rosaniline 
hydrochloride  dissolved  in  methylated  spirit  or  methyl  alcohol 
under  pressure,  it  was  found  that  a  very  beautiful  purple  or 
violet  colouring  matter  could  be  produced ;  the  process  was 
patented  in  1864,  and  large  quantities  of  a  colouring  matter, 
known  as  Britannia  violet,  were  prepared  in  this  manner.  At 
first  it  was  thought  that  the  hydrocarbon  radicle  of  the  brominated 
turpentine  entered  the  rosaniline,  but  it  now  appears  most 
probable  that  the  product  consisted  of  methylrosanilines  produced 
by  the  action  of  methyl  bromide  formed  from  hydrogen  bromide 
resulting  from  the  decomposition  of  the  bromo  compound. 
The  colouring  matter  was  more  soluble  than  Hofmann's  ethyl 
violet,  but  I  could  not  succeed  in  crystallising  it,  and,  therefore, 
it  was  not  subjected  to  analysis. 

When  the  base  of  Britannia  violet  is  acted  on  by  acetyl 
chloride,  two  products  are  obtained,  namely,  a  violet  colouring 
matter  much  bluer  in  shade  than  the  original  violet,  and  a  bluish- 
green  compound.  The  base  of  this  latter  has  a  very  feeble 
affinity  for  acids,  and  does  not  combine  with  acetic  acid,  whilst 
the  base  of  the  violet  compound  does  so  freely,  and  in  virtue  of 
these  different  properties  the  two  colouring  matters  are  easily 
separated.  The  green  dye  proved  to  be  of  practical  value,  and 
considerable  quantities  of  it  were  prepared  for  the  calico  printers. 
It  was  known  as  Perkin's  green,  but  after  a  time  it  was  displaced 
by  iodine  green.  It  has  not  hitherto  been  investigated.  For 
its  manufacture,  large  quantities  of  terchloride  of  phosphorus 
were  prepared,  from  which  and  acetic  acid  large  quantities  of 
acetyl  chloride  were  made — another  instance  of  the  use  of  a 
research  reagent  on  the  large  scale. 

The  last  investigation  relating  to  colouring  matters  carried  out 
by  Hofmann  in  this  country  was  that  of  the  very  interesting  sub- 
stance known  as  quinoline  blue,  discovered  by  Greville  Williams, 
of  which  the  latter  gave  an  account  in  the  Chemical  News  for 


HOFMANN   MEMORIAL   LECTURE  167 

nth  October  1860  (p.  219).  A  beautiful  specimen  of  the 
crystallised  substance  was  displayed  in  the  exhibition  of  1862 
under  the  name  of  cyanin.  Quinoline  blue  was  a  very  pure 
shade  of  colour,  and,  although  an  expensive  product,  attempts 
were  made  to  introduce  it  as  a  dye  ;  unfortunately,  although  pro- 
duced from  bases  of  remarkable  stability,  it  was  very  fugitive, 
goods  dyed  with  it  fading  very  quickly  indeed  when  exposed  to 
the  light  —  its  sensitiveness  being  so  great  that  on  placing  it  under 
a  glass  positive  photograph  and  exposing  to  sunlight,  after  only 
a  short  time  a  quinoline  blue  positive  picture  was  produced. 

Hofmann  separated  from  quinoline  two  blue  compounds,  to 
one  of  which  he  gave  the  formula  CaoH^g^I,  and  to  the  other 
the  formula  C28H35N2I.  According  to  later  researches,  the  blue 
is  a  condensation  product  derived  from  quinoline  amyliodide  and 
lepidine  amyliodide. 

C29H35N2I  +  H2O  +  HI 


Quinoline  amyl  Lepidine  amyl  Cyanine  or  diamyl 

iodide.  iodide.  cyanine  iodide. 

This  formula  differs  from  that  given  by  Hofmann  to  one  of 
the  products  he  examined  by  an  atom  of  carbon  only. 

After  I  left  the  Royal  College  of  Chemistry,  the  researches 
on  the  phosphorus  bases  in  which  I  had  been  helping  were  con- 
tinued by  Drs  Leibius  and  Holzmann,  to  whose  able  assistance 
Hofmann  refers  in  one  of  his  papers  ;  but  in  carrying  out  the 
part  of  this  work  relating  to  the  phosphammonium,  phosph- 
arsonium,  and  arsammonium  compounds,  another  assistant  was 
active,  who  is  referred  to  by  Hofmann  in  the  following  words  :  — 

"  I  conclude  this  memoir  with  the  expression  of  my  best 
thanks  for  the  untiring  patience  with  which  Mr  Peter  Griess 
has  assisted  me  in  the  performance  of  my  experiments  on  the 
phosphorus  bases.  The  truly  philosophical  spirit  in  which  this 
talented  chemist  has  accompanied  me  through  the  varying 
fortunes  of  this  inquiry,  will  always  be  one  of  my  pleasing 
recollections." 

We  know  how  the  high  opinion  thus  expressed  by  Hofmann 
of  Griess  not  only  lasted,  but  became  enhanced  as  time  went  on  ; 
and  although  Griess  was  not  one  of  Hofmann's  pupils,  I  cannot 
refrain  from  thus  referring  to  him  here,  as  several  of  his  most 
important  early  researches  on  the  diazo  compounds  were  made 
within  the  walls  of  the  Royal  College  of  Chemistry,  thereby  con- 
necting this  Institution  with  work  which  of  late  years  has  had 


1 68         THE   BRITISH    COAL-TAR   INDUSTRY 

such  a  marvellous  influence  on  the  development  of  the  coal-tar 
colour  industry.  But  it  is  not  my  intention,  nor  indeed  is  it 
necessary  for  me,  to  go  into  the  history  of  the  diazo  compounds, 
as  this  has  been  so  very  ably  done  by  my  friend  Caro  in  his 
memoir  of  Peter  Griess,  whom  he  held  in  such  high  esteem,  and 
who  was  also  one  of  his  greatest  friends. 

Hofmann's  departure  was  not  only  a  cause  of  regret  to  those 
who  had  worked  under  him  and  to  all  his  friends  ;  it  was  a 
heavy  loss  also  to  the  country  at  large,  as  no  one  had  ever  done 
so  much  for  the  cause  of  chemical  science  in  the  kingdom  as 
Hofmann  did,  nor  had  anyone  exercised  to  such  an  extent  that 
wonderful  power  he  possessed  of  stimulating  the  enthusiasm  of 
his  students  and  of  inciting  in  them  a  love  of  chemistry  and  of 
scientific  research.  His  success  is  especially  striking  when  the 
early  history  of  the  Royal  College  of  Chemistry  is  taken  into 
account — especially  its  financial  difficulties,  the  dissatisfaction  of 
some  of  the  subscribers,  and  the  want  of  understanding  as  to  the 
value  of  scientific  research  shown  both  by  them  and  the  public  at 
large.  When  all  these  circumstances  are  considered,  we  cannot 
but  marvel  at  the  courage  and  indomitable  determination  he  dis- 
played, which  enabled  him  to  overcome  all  difficulties  and  to  per- 
severe in  maintaining  the  high  standard  of  teaching  he  adopted 
at  the  beginning,  as  well  as  to  continue  the  prosecution  of  scientific 
research  for  its  own  sake. 

Notwithstanding  the  immense  amount  of  work  Hofmann 
must  have  had  to  attend  to  in  connection  with  the  building 
and  fitting  up  of  the  new  chemical  laboratories  of  the  Frederick 
William  University  of  Berlin,  which  took  place  during  the  first 
four  years  after  he  left  England,  namely,  from  May  1865  to 
May  1869,  no  break  occurred  in  his  scientific  activity,  each  year 
producing  accounts  of  fresh  work  accomplished.  It  was  not, 
however,  until  1869  that  he  published  anything  fresh  in  con- 
nection with  the  coal-tar  colours,  but  in  this  year  several  com- 
munications appeared. 

Having  found  that  the  production  of  rosaniline  depended 
on  the  presence  of  two  bases,  aniline  and  toluidine,  he  naturally 
carried  his  investigation  of  the  subject  further,  and  experimented 
with  xylidine  (meta).  However,  on  heating  this  base  with  oxidis- 
ing agents,  either  alone  or  in  presence  of  toluidine,  no  colouring 
matter  was  obtained  ;  but  when  it  was  heated  with  pure  aniline, 
a  red  was  formed,  which  he  called  xylidine  red,  which  was  supposed 


HOFMANN    MEMORIAL   LECTURE  169 

to  be  a  homologue  of  rosaniline,  probably  of  the  composition 
C22H25N3O.  The  colour  produced  on  wool  and  silk  by  this 
dyestuff  was  almost  as  bright  as  that  of  rosaniline  itself  (Ber.^  2, 
377).  In  a  second  paper  relating  to  this  subject,  published  in 
conjunction  with  Martius  (Ber.y  2,  411),  an  account  is  given  of 
similar  experiments  with  an  isomer  of  xylidine,  amidoethylbenzene, 
which,  from  the  more  recent  researches  of  Beilstein  and  Kilhlberg 
(Zeitsch.  f.  Chem.  [2],  5,  524),  we  now  know  must  have  been  a 
mixture  of  the  ortho  and  para  compounds.  No  red  colouring 
matter  was  formed  from  this  on  boiling  it  with  an  oxidising 
agent,  either  alone  or  mixed  with  toluidine  or  even  with  aniline, 
thus  affording  proof  of  the  interesting  fact  that  an  ethyl  group 
cannot  take  the  place  of  a  methyl  group  in  the  interaction  which 
is  involved  in  the  production  of  colouring  matters  of  the  rosani- 
line class. 

After  the  discovery  of  mauve  and  magenta,  many  experi- 
ments were  made  with  a-naphthylamine,  as  a  source  of  colouring 
matter,  and  a  variety  of  products  was  obtained  and  patented  ; 
but  it  is  unnecessary  for  me  to  enter  into  an  account  of  these 
here,  as  most  of  them  were  found  to  be  of  no  technical  value. 
I  may,  however,  allude  to  two  naphthalene  derivatives  which 
have  proved  useful  ;  the  first  of  these,  naphthazarin,  was  dis- 
covered by  Roussin  in  1861,  who  thought  it  was  artificial  alizarin. 
This  beautiful  substance,  which  is  now  known  to  be  a  dihydroxy- 
/3-naphthoquinone,  lay  dormant  for  a  long  time,  but,  owing  to 
the  discovery  of  improved  methods  of  producing  it,  has  of  late 
come  into  use  for  dyeing  black  on  wool.  The  second  was  dis- 
covered by  Martius,  and  is  known  as  "  Martius  yellow "  or 
dinitro-a-naphthol.  These  were  the  principal  colouring  matters 
derived  from  naphthalene  known  prior  to  1867,  when  Schiendl 
discovered  the  naphthalene  red  now  known  by  the  name  of 
Magdala  red,  a  substance  remarkable  for  the  beautiful  fluor- 
escence of  its  solution.  The  original  process  for  its  preparation 
consisted  in  heating  naphthylamine,  acetic  acid,  and  potassium 
nitrite  together,  and  then  adding  more  naphthylamine  and  again 
heating  until  the  desired  colouring  matter  was  produced. 

Hofmann  investigated  this  red,  and  assigned  to  it  the  formula 
C30H21N3  (Ber.,  1869,  2,  374). 

As  this  colouring  matter  and  the  above  formula  appeared 
to  be  related  to  an  old  friend  of  mine,  azodinaphthyldiamine 
(amidoazonaphthalene),  I  made  it  the  subject  of  experiments, 


i  yo         THE   BRITISH   COAL-TAR   INDUSTRY 

and  found  that  it  was  easily  produced  on  heating  amidoazo- 
naphthalene  with  an  acid  and  naphthylamine,  an  action  taking 
place  which  it  was  thought  involved  the  displacement  of  an  atom 
of  hydrogen  by  naphthyl  and  the  formation  of  ammonia  : 

C20H15N3  +  C10H9N  =  C30H21N3  +  NH3. 

Amidoazo-  Magdala  red. 

naphthalene. 

The  colouring  matter  was  called  azotrinaphthyldiamine  (Proc. 
Roy.  Int.,  I4th  May  1869). 

In  a  second  paper,  published  in  July  of  the  same  year,  on  the 
nature  of  naphthalene  red,  Hofmann  confirms  my  observations 
(Ber.,  2,  413). 

It  has  since  been  shown,  however,  by  Julius  (Ber.,  1886, 
19,  1365),  that  the  action  which  occurs  when  amidoazo- 
naphthalene  is  treated  with  naphthylamine  is  not  nearly  so 
simple  as  above  indicated,  and  that  the  formula  of  the  hydro- 
chloride  of  Magdala  red  is  C30H2iN4Cl,  not  C30H22N3C1. 

The  research  on  Magdala  red  led  Hofmann  to  study  the 
compound  produced  by  the  action  of  aniline  on  amidoazobenzene, 
a  substance  described  by  Martius  and  Griess,  but  discovered  by 
Dale  and  Caro  in  1863,  and  called  by  them  induline.  The  ex- 
amination of  this  product  was  afterwards  continued  by  Hofmann 
in  conjunction  with  Geyger,  under  the  heading  of  colouring 
matters  obtained  from  aromatic  azodiamines,  and  published  in 
1872  (Ber.,  5,  472).  They  called  this  substance  azodiphenyl 
blue,  and  showed  that  its  hydrochloride  had  the  formula 
C18H16N3C1. 

In  1869  Hofmann  also  continued  his  researches  on  chrys- 
aniline,  studying  the  action  of  methyl  and  ethyl  iodide  on  the 
base  ;  he  obtained  trimethyl  and  triethyl  substitution  products 
(•Ber.,  2,  378). 

In  preparing  Hofmann  violet,  it  was  found  that  on  precipi- 
tating the  colouring  matter  from  its  aqueous  solution  by  means 
of  sodium  chloride,  a  certain  quantity  of  a  bluish-green  product 
remained  in  solution  which  could  not  be  separated  (though  im- 
proved in  colour)  by  the  addition  of  sodium  carbonate  ;  this  was 
precipitated  by  means  of  picric  acid,  and  as  it  proved  to  be  a 
valuable  green  dye,  it,  after  a  time,  was  supplied  in  small 
quantities  to  dyers  under  the  name  of  iodine  green.  It  was  then 
found  by  J.  Keisser  (French  patent,  i8th  April  1866)  that  the 
colouring  matter  could  be  obtained  in  much  larger  quantities  by 


HOFMANN    MEMORIAL   LECTURE  171 

methylating  rosaniline,  dissolved  in  methyl  alcohol,  with  methyl 
iodide,  the  operation  being  completed  at  a  comparatively  low 
temperature,  and  eventually  it  was  obtained  in  a  pure  crystallised 
state.  This  substance  being  evidently  related  to  the  methyl- 
rosanilines,  Hofmann  was  naturally  interested  in  it,  and  with 
Girard  undertook  its  investigation  (Ber.,  2,  440). 

The  results  they  obtained,  on  analysing  the  iodo  compound, 
led  them  to  represent  it  by  the  formula 


Cao^ie  I  >j 
(CH8)8/JN 


f  CH8I. 
CH.I.H0. 


They  found  that  this  compound  decomposes  when  heated  at 
the  temperature  of  boiling  water  for  a  few  hours,  and  instantly  at 
130°—  150°  C.,  becoming  changed  into  a  violet  colouring  matter  ; 
in  fact,  it  behaves  like  an  ammonium  or  addition  product.  As 
the  complicated  history  of  the  methyl  and  ethyl  derivatives 
developed,  it  was  found  that  the  formula  above  given  required 
to  be  modified  to  some  extent  ;  but  this  is  in  no  way  surprising, 
as  it  is  practically  impossible  by  analysis  alone  to  arrive  at  a  true 
conclusion  as  to  the  constitution  of  a  compound  of  such  high 
molecular  weight,  so  unstable  and  so  difficult  to  obtain  pure. 

Another  green  dyestuff  to  which  Hofmann  directed  his 
attention  at  this  time  was  aldehyde  green,  produced  by  the  action 
of  aldehyde  on  rosaniline  in  presence  of  sulphuric  acid,  whereby 
a  blue  colouring  matter  is  formed,  which  is  transformed  into 
the  green  by  the  action  of  an  aqueous  solution  of  sodium  thio- 
sulphate.  Lauth,  apparently,  was  the  first  to  produce  the  blue 
compound,  in  1861,  by  subjecting  a  solution  of  rosaniline  in 
alcohol,  methyl  alcohol,  acetic  acid,  or  acetone  to  the  action  of 
zinc  chloride  and  other  metallic  salts,  but  the  conversion  of  the  blue 
into  the  green  was  accomplished  by  Cherpin  in  1862.  This  was 
the  first  aniline  green  dye  discovered  (emeraldine,  which  was  of 
no  value,  excepted),  and  was  much  used.  Hofmann  showed  that 
aldehyde  green  contained  sulphur,  and  assigned  to  it  the  com- 
position indicated  by  the  formula  C22H27N3S2O,  representing 
its  formation  by  the  following  equation, 

C20H19N3  +  C2H4O  +  2H2S  =  C22H27N8S2O 

(Bcr.,  1870,3,761). 

The  next  researches  it  will  be  most  convenient  to  refer  to, 
though  not  quite  the  next  as  to  date,  are  those  on  the  methyl 


172         THE   BRITISH   COAL-TAR   INDUSTRY 

violets  ;  but,  before  considering  these  it  may  be  mentioned  that, 
in  continuation  of  his  researches  on  rosaniline  derivatives, 
Hofmann,  in  1873  (Ber.,  6,  263),  examined  the  violet  obtained 
by  Hobrecker  by  the  action  of  benzyl  chloride  and  methyl  iodide 
on  a  solution  of  rosaniline  in  methyl  alcohol,  assigning  to  it  the 
formula  C2oH16(C7H7)3N3CH3I. 

Until  long  after  the  commencement  of  the  coal-tar  colour 
industry,  chemists  and  experimenters  directed  their  attention 
chiefly  to  aniline  as  a  source  of  colouring  matter  ;  but  in  1861 
Lauth  made  some  experiments  on  the  product  Hofmann  obtained 
by  acting  with  methyl  iodide  on  aniline,  which  he  described  as 
methylaniline  (Jour.  Chem.  Soc.,  1851,  3,  296),  but  which  recent 
researches  have  shown  is  a  mixture  of  methylaniline  and  di- 
methylaniline,  and  by  oxidising  this  he  obtained  violet  colouring 
matters.  Writing  of  these  in  1867,  Lauth  says  (Laboratory, 
1867,  138),  "The  violets  obtained  from  methylaniline  possess 
a  richness  and  purity  which  leave  nothing  to  be  desired.  .  .  . 
Nevertheless,  they  were  not  adopted  by  manufacturers,  who, 
indeed,  at  the  time  mentioned  (1861)  attached  less  importance 
to  the  beauty  of  a  colour  than  to  its  permanence.  In  this  latter 
respect  the  methylaniline  violets  do  not  excel,  and,  consequently, 
dyers  would  have  nothing  to  do  with  them.  Gradually,  how- 
ever, people  have  become  accustomed  to  colours  which  fade  on 
exposure  to  the  solar  rays.  .  .  .  Accordingly,  two  years  after  the 
experiment  made  by  myself,  Dr  Hofmann  succeeded  in  introduc- 
ing these  results." 

These  remarks  confirm  those  already  made  in  reference  to  the 
gradual  change  in  public  opinion  which  led  to  the  disregard  of 
permanency  in  favour  of  brilliancy  of  colour. 

Lauth  further  remarks  that  Hofmann's  method  of  producing 
these  colouring  matters  is  the  inverse  of  that  proposed  by  him  ;  the 
aniline  being  first  converted  into  rosaniline  and  then  methylated, 
whilst  in  his  case  this  operation  is  first  performed  on  the  aniline. 

It  would,  however,  not  have  been  practicable  to  carry  out 
this  process  if  the  aniline  had  to  be  methylated  with  methyl 
iodide,  because  the  base  thus  prepared  would  be  too  expensive 
to  use  as  the  raw  material  for  the  preparation  of  colouring 
matters.  On  account  of  the  success  of  the  Hofmann  violet, 
experiments  were  made  in  France  with  the  object  of  preparing 
methylaniline  by  a  different  and  more  economical  process,  so  as 
to  commercially  produce  Lauth's  violet,  and  this  was  at  that  time 


HOFMANN    MEMORIAL   LECTURE  173 

considered  especially  desirable  by  some  manufacturers,  because 
the  production  of  rosaniline  in  France  was  the  monopoly  of  one 
house,  and,  therefore,  derivatives  of  this  colouring  matter  could 
not  be  economically  made  by  others. 

Eventually  a  successful  process  was  discovered  by  M.  Bardy, 
chemist  to  the  firm  of  Poirrier  &  Chapat,  which  consists  in 
heating  a  mixture  of  aniline  hydrochloride  and  methyl  alcohol 
in  a  closed  vessel  to  a  high  temperature.  As  is  now  well  known, 
though  not  at  first  recognised,  this  process  yields  a  mixture  of 
mono-  and  di-methylaniline,  consisting  chiefly  of  the  latter. 
Large  quantities  of  methylated  aniline  were  soon  produced  by 
this  process,  and  used  in  the  preparation  of  a  violet  colouring 
matter  which  was  manufactured  by  Messrs  Poirrier  &  Chapat, 
and  called  by  them  violet  de  Paris ;  a  large  block  of  this, 
weighing  about  150  kilos,  was  exhibited  in  the  Paris  Exhibi- 
tion of  1867.  The  question  then  arose  as  to  whether  violet  de 
Paris  was  identical  or  isomeric  with  methylrosaniline  violet. 
Lauth  considered  that  it  was  isomeric,  and  remarks  :  u  Hofmann 
violets  consist  of  methylated  and  ethylated  rosaniline,  and 
rosaniline  is  derived  from  a  molecule  of  aniline  and  two  molecules 
of  toluidine.  The  violet  de  Paris,  on  the  contrary,  is  produced 
from  pure  aniline  free  from  toluidine,  transformed  into  methyl- 
aniline,  which  is  isomeric  with  toluidine.  This  methylaniline 
when  oxidised  is  converted  into  the  violet,  which  may  have  a 
composition  analogous  to  that  of  methylated  rosaniline,  but  must 
differ  from  the  latter  in  the  same  manner  as  methylaniline  differs 
from  toluidine." 

Hofmann,  being  naturally  interested  in  the  relationship  of 
these  colouring  matters,  investigated  the  subject,  and  published 
his  results  in  1873  (for.,  6,  352).  He  first  studied  the 
conditions  under  which  the  colouring  matter  could  be  formed, 
showing  that  violet  could  be  produced  from  pure  dimethylaniline 
obtained  by  the  distillation  of  trimethylammonium  hydrate  ;  he 
also  came  to  the  conclusion  from  the  examination  of  the  colouring 
matter  that  it  was  a  methylchlorhydrate  of  trimethylrosaniline  : — 

C20H16(CH8)3N3.CH3.C1, 
the  base  being 

C20H16(CH3)3N3.CH3.OH. 

He  prepared  iodine  green  by  methylating  this  compound  ; 
also  its  leuco  compound. 


174         THE   BRITISH    COAL-TAR   INDUSTRY 

This  research  must  have  been  a  very  difficult  and  laborious 
piece  of  work,  and  although  Hofmann's  views  as  to  the  constitu- 
tion of  the  dimethylaniline  violet  are  not  those  now  accepted, 
the  accuracy  of  his  work  has  not  been  impugned. 

The  long  controversy  which  arose,  soon  after  the  time  when 
Hofmann  published  his  constitutional  formula  of  rosaniline,  as 
to  the  constitution  of  this  colouring  matter,  belongs  to  another 
chapter,  and  need  not  be  referred  to  here. 

Mention  has  already  been  made  of  the  process  for  methylating 
aniline  discovered  by  Bardy,  which  consisted  in  heating  this  base 
with  hydrochloric  acid  and  methyl  alcohol.  In  1871  Hofmann 
and  Martius  (Ber.,  4,  742)  made  some  experiments  in  reference 
to  this  method,  working  at  higher  temperatures  than  those  usually 
employed  (28o°-3OO°  C.),  and  continuing  the  heating  for  a  con- 
siderable time  ;  in  this  way  they  obtained,  besides  methyl,  and 
dimethylaniline,  a  quantity  of  basic  oil  of  higher  boiling-point, 
which  eventually  proved  to  be  a  complex  mixture  of  methylated 
homologues  of  dimethylaniline,  the  products  of  an  intramolecular 
change  or  atomic  wandering. 

These  remarkable  researches,  like  so  many  other  purely 
scientific  discoveries,  ere  many  years  had  passed,  were  found  to 
be  of  technical  value  in  connection  with  the  coal-tar  colour  in- 
dustry, the  cumidine  that  is  so  extensively  used  in  the  preparation 
of  some  of  the  diazo  colours  being  made  by  the  method  of  Hof- 
mann and  Martius  by  heating  xylidine  with  hydrochloric  acid  and 
methyl  alcohol  to  a  high  temperature,  about  300°  C. 

Reverting  once  more  to  the  early  days  of  the  coal-tar  colour 
industry,  I  may  now  mention  that  the  liquors  from  which  mauve 
was  precipitated  were  found  to  contain  a  red  colouring  matter 
which  I  succeeded  in  separating,  although  the  amount  obtainable 
was  very  small.  This  proved  to  be  a  beautiful  dye  producing 
crimson-red  shades  on  silk.  It  was  afterwards  discovered  that 
it  could  be  produced  by  the  oxidation  of  mauveine,  and  it  was 
prepared  in  considerable  quantity  in  this  way,  but  was  a  very 
expensive  product,  and  therefore  not  very  largely  used.  This 
dyestuff  was  known  first  as  "aniline  pink,"  and  afterwards  as 
"  safranine."  In  1865  a  colouring  matter  having  the  properties 
of  safranine  was  produced  without  the  use  of  mauveine  by  F. 
Duprey,  by  heating  commercial  aniline  dissolved  in  acetic  acid 
with  lead  nitrate.  It  was  then  obtained  by  acting  on  commercial 
aniline  with  nitrous  acid  and  oxidising  the  mixture  with  arsenic 


HOFMANN    MEMORIAL   LECTURE  175 

acid.  The  colouring  matter  prepared  in  this  way  was  examined 
by  Hofmann  and  Geyger  (Ber.,  1872,  5,  531).  They  found 
it  to  be  a  base  forming  crystalline  salts,  among  others  a  hydro- 
chloride  having  the  composition  C^i^iN^CL  As  they  found 
that  it  could  not  be  produced  from  either  aniline  or  paratoluidine, 
or  a  mixture  of  the  two,  but  from  orthotoluidine,  they  regarded 
it  as  a  toluidine  derivative.  They  also  observed  that  the  formula 
above  given  differs  from  that  of  mauveine  by  C6H4,  making  it 
appear  possible  that  mauveine  was  phenylsafranine.  In  the 
course  of  an  investigation  of  the  safranine,  obtained  by  the 
oxidation  of  mauveine,  of  which  I  published  an  account  some 
time  after  this  (Jour.  Chem.  Soc.,  1879,  35,  728),  this  substance 
was  shown  to  form  a  hydrochloride  represented  by  the  formula 
C20H18N4,  which  differs  from  that  of  the  substance  examined  by 
Hofmann  and  Geyger  by  CH2.  On  examining  a  commercial 
product  manufactured  by  Messrs  Guinon  &  Co.,  of  Lyons,  from 
commercial  aniline,  both  substances  were  found  to  be  present, 
showing  that  two  "  safranines  "  existed,  and  I  then  also  showed 
that  probably  a  third  was  formed  by  the  oxidation  of  pseudo- 
mauveine. 

The  formula  of  the  safranine  hydrochloride  obtained  from 
mauveine  will  be  seen  from  the  above  to  differ  from  mauveine 
by  C7H6,  so  that  the  relationship  of  these  substances  is  probably 
not  of  so  simple  a  character  as  Hofmann  and  Geyger  supposed, 
though,  of  course,  C7H6  may  simply  mean  displacement  of 
hydrogen  by  tolyl.  No  doubt  a  great  similarity  exists  between 
them,  one  proof  of  which  is  that  their  behaviour  with  sulphuric 
acid  is  analogous.  This  applies  both  to  those  referred  to  above 
and  to  the  third  compound  since  discovered. 

In  1875  Hofmann  made  an  examination  of  eosin  (Ber.,  8,  62), 
and  thus  disclosed  to  the  world  an  important  manufacturing 
secret,  proving  to  demonstration  the  impossibility  in  these  days 
of  long  hiding  from  chemists  the  nature  of  any  substance,  how- 
ever complex.  Eosin,  as  is  well  known,  was  the  first  representa- 
tive of  a  new  class  of  colouring  matters  which  has  since  become 
of  great  importance. 

Chrysoidine,  which  may  fairly  be  termed  the  parent  of  an 
even  more  important  class  of  colouring  matters,  the  azo  dyes, 
the  introduction  of  which  marks  a  new  era  in  this  branch  of 
chemistry,  was  investigated  and  publicly  proclaimed  by  Hofmann 
in  1877  (Ber.,  10,  213). 


176         THE   BRITISH   COAL-TAR   INDUSTRY 

The  colouring  matter  to  which  he  next  directed  his  attention 
was  pittacal,  also  called  euppitonic  acid,  the  interesting  compound 
discovered  by  Reichenbach,  as  far  back  as  1835,  produced  from 
wood  tar.  Hofmann  (Ber.,  1878,  11,  1655  ;  1879, 12,  1371  and 
2216)  was  led  to  regard  this  substance  as  hexamethoxyrosolic 
acid,  C19H8(OCH3)6O3  ;  on  treating  it  with  ammonia,  he 
obtained  a  beautiful  blue  dyestuff,  thus, 

C25H2609  +  3H3N  =  C25H31N3060  +  2<DH2, 
which  he  regarded  as  hexamethoxypararosaniline, 

C19H13(OCH3)6N30. 

He  then  made  the  interesting  discovery  that  the  formation 
of  pittacal,  or  euppitonic  acid,  from  dimethylpyrogallate  and 
dimethyl-methylpyrogallate  took  place  in  a  manner  analogous 
to  that  in  which  pararosaniline  was  formed,  thus, 

2  .  C6H7N  +  C7H9N  =  C19H17N3  +  H32. 

Aniline.       Toluidine.     Pararosaniline. 

2C8H10O3     +     C9H12O3     =     C25H26O9     +     3H2, 

Dimethyl-  Dimethyl-methyl-          Pittacol  or 

pyrogallate.  pyrogallate.  euppitonic  acid. 

a  comparison  which  is  of  considerable  interest. 

Hofmann's  last  research  in  connection  with  the  coal-tar 
colour  industry  was  made  as  late  as  1887,  and  related  to  the 
quinoline  red  prepared  by  Jacobson,  in  1882,  from  coal-tar 
quinoline,  benzotrichloride,  and  zinc  chloride.  Hofmann,  how- 
ever, found  that  a  better  yield  of  colouring  matter,  either 
identical  or  isomeric  with  Jacobson's,  is  obtained  by  using  a 
mixture  of  isoquinoline  and  quinaldine.  Like  quinoline  blue 
or  cyanine,  the  colour  is  not  a  fast  one,  which  as  previously 
mentioned,  is  remarkable,  considering  the  stability  of  quinoline 
itself.  It  is  a  somewhat  remarkable  coincidence  that  this  should 
have  been  the  last  research  Hofmann  made  on  the  coal-tar 
colours,  as  quinoline  (or  leucoline)  was  one  of  the  two  substances 
he  gave  an  account  of  in  his  first  investigation  published  in  1843, 
when  thirty  years  of  age. 

Excepting  what  is  said  of  pittacal,  and  the  brief  reference  to 
eosin  and  chrysoidine,  the  foregoing  account  has  reference  only 
to  what  may  be  termed  aniline  colours,  the  great  chapter  dealing 
with  the  history  of  technical  chemistry,  with  which  Hofmann's 
name  is  indissolubly  linked. 


HOFMANN   MEMORIAL   LECTURE  177 

An  entirely  new  chapter  in  coal-tar  chemistry  opens  in  1868, 
when  Graebe  and  Liebermann  (in  connection  with  their  re- 
searches on  quinones)  made  their  great  discovery  of  the  artificial 
formation  of  alizarin  from  anthracene.  They  patented  their 
process  in  Germany  in  October,  and  in  this  country  on  i8th 
December  of  that  year.  Their  process,  it  is  well  known,  con- 
sisted in  producing  dibromanthraquinone,  either  by  brominating 
anthraquinone  in  sealed  tubes,  or  by  oxidising  tetrabrom- 
anthracene,  and  subsequently  displacing  bromine  by  hydroxyl, 
by  fusion  with  alkali. 

This  discovery  for  the  first  time  of  a  method  of  obtaining 
a  vegetable  colouring  matter  artificially  was,  however,  as  it  stood, 
of  no  practical  value,  as  such  a  process  could  not  be  carried  out 
on  a  large  scale. 

But  why  should  this  be  mentioned  here  ?  It  may  seem  that 
any  reference  to  the  alizarin  industry  is  out  of  place  in  a  notice 
designed  to  elucidate  Hofmann's  influence  on  the  development 
of  our  knowledge  of  products  derived  from  coal-tar,  as  he 
apparently  never  took  any  part  in  the  investigation  of  anthracene 
derivatives.  Yet  it  is  to  his  influence  that  I  can  trace  back  my 
interest  in  the  subject,  for,  as  mentioned  early  in  this  account, 
the  very  first  subject  in  research  which  he  suggested  to  me  was 
to  prepare  a  nitro  compound  and  a  base  from  anthracene.  In 
the  course  of  this  work  I  not  only  became  thoroughly  acquainted 
with  this  hydrocarbon,  but  also  prepared  anthraquinone  and 
other  derivatives  of  it,  and  consequently  was,  perhaps,  more 
fully  prepared  than  any  other  chemist  of  the  day  to  appreciate 
the  discovery  of  the  relationship  of  alizarin  to  anthracene,  and 
was  naturally  impelled  at  once  to  attempt  to  adapt  it  to  practical 
requirements.  It  is  more  than  probable  that  I  should  have  paid 
but  ordinary  attention  to  Graebe  and  Liebermann's  work  had  I 
not  possessed  an  early  attachment  to  anthracene,  and  I  am  glad 
to  recognise  that  I  owe  this  to  the  knowledge  and  insight  of  my 
great  master. 

Being  aware  of  the  importance  of  alizarin  as  a  colouring 
matter,  and  having  some  quantity  of  anthracene  and  anthra- 
quinone left  over  from  my  experiments  at  the  Royal  College 
of  Chemistry,  I  commenced  to  experiment  on  the  formation  of 
this  substance,  with  the  object  of  finding  a  process  by  which 
bromine  might  be  dispensed  with. 

I  knew  of    the  remarkable  stability  of  anthraquinone  :  that 

12 


178          THE   BRITISH   COAL-TAR   INDUSTRY 

it  could  be  crystallised  from  concentrated  sulphuric  acid  without 
undergoing  change,  and  that  in  making  a  combustion  of  it,  if 
the  operation  were  at  all  hurried,  part  of  the  anthraquinone 
would  pass  through  the  heated  tube,  and  condense  at  the  cool 
end  unaltered. 

Moreover,  not  long  before  I  commenced  to  work  at  the 
artificial  formation  of  alizarin,  namely,  in  1867,  Wilrtz  and 
Kekule  had  shown  that  when  benezenesulphonic  acid  was  heated 
with  potassium  hydrate,  it  gave  a  phenate  and  sulphite  ;  and 
Dusart  had  also  found  that  naphthalenedisulphonic  acid  was  in 
like  manner  converted  into  a  dihydroxynaphthalene  ;  so  that  it 
appeared  probable  that  if  a  disulphonic  acid  of  anthraquinone 
could  be  obtained,  it  would  be  possible  to  convert  it  by  the 
new  reaction  into  alizarin. 

Anthraquinone  was  therefore  heated  with  oil  of  vitriol  more 
and  more  strongly,  until  the  boiling-point  was  nearly  reached,  as 
I  was  determined  either  to  obtain  a  sulphonic  acid  or  destroy  the 
anthraquinone  ;  and  at  last  it  was  found  that  the  anthraquinone 
had  disappeared,  yielding  a  product  which  was  soluble  in  water. 
After  the  excess  of  sulphuric  acid  had  been  removed  in  the  usual 
way  with  barium  carbonate,  the  product  was  fused  with  caustic 
alkali,  and  to  my  delight  it  changed  first  to  violet,  and  then 
became  black  from  the  intensity  of  its  colour.  On  dissolving 
the  melt,  a  beautiful  purple  solution  was  obtained,  which  gave  a 
yellow  precipitate  when  acidified,  and  on  examination  this  was 
found  to  dye  mordanted  cloth  like  garancine. 

On  the  2oth  of  May  (1869)  I  sent  dyed  patterns  to  my  friend 
Mr  Robert  Hogg,  of  Glasgow,  who  had  a  very  large  experience 
in  reference  to  madder  and  garancine,  and  also  of  the  coal-tar 
colours  from  the  days  of  the  mauve  dye,  whose  opinion  I  valued 
very  much  in  all  practical  matters  connected  with  dye-stuffs, 
especially  from  a  commercial  point  of  view,  and  he  was  very 
favourably  impressed  with  the  results  I  had  obtained.  This 
process,  however,  was  not  patented  until  26th  June.  (About 
the  same  time  as  I  discovered  this  process,  Graebe,  Liebermann, 
and  Caro  quite  independently  arrived  at  the  same  result  in 
Germany.)  This  process  has  proved  the  most  permanently 
important  one  yet  discovered,  and  is  the  one  still  universally 
used.  I  was  also  fortunate  enough  to  discover  a  second  process, 
which  was  of  great  value  in  the  early  days  of  the  industry,  but  is 
not  in  use  now  so  far  as  I  know.  It  consisted  in  the  use  of 


HOFMANN   MEMORIAL  LECTURE  179 

dichloranthracene  as  the  starting-point,  instead  of  anthraquinone. 
This  substance  was  found  to  readily  afford  a  sulphonic  acid, 
which  could  be  easily  changed  into  anthraquinonesulphonic  acid, 
either  by  oxidising  its  solution  with  manganese  dioxide  or  more 
simply  by  heating  it  with  sulphuric  acid.  This  process  was 
patented  in  November  1869. 

After  discovering  processes  by  which  artificial  alizarin  could 
be  produced,  the  technical  value  of  the  artificially  prepared  dye- 
stuff  had  to  be  ascertained.  Experiments  were  soon  made  by 
the  calico  printers,  as  no  new  processes  had  to  be  discovered  for 
the  application  of  this  colouring  matter,  those  in  use  for  madder 
and  garancine  being  suitable.  Turkey-red  dyers  also  experi- 
mented with  it,  but  some  were  not  so  successful  as  others,  for 
reasons  easily  understood  afterwards,  when  the  properties  of 
anthrapurpurin,  which  it  contained,  were  better  known. 

The  subject  of  price,  however,  was  the  important  question, 
because  this  product  had  to  compete  with  those  already  in  the 
market,  namely,  madder  and  garancine,  and  therefore  high  prices 
could  not  be  obtained  as  in  the  case  of  a  new  dye. 

Before  this  could  be  settled,  the  first  thing  necessary  was  to 
get  a  supply  of  anthracene.  This  substance  was  not  at  this  date 
separated  by  the  tar  distillers,  there  being  no  use  for  it  ;  many  of 
them,  in  fact,  knew  nothing  of  its  existence,  and  the  question  as 
to  whether  it  could  be  obtained  in  sufficient  quantity  and  at  a 
sufficiently  low  price  had  to  be  settled. 

But  experiments  I  had  made  on  the  small  scale,  on  the  dis- 
tillation of  soft  pitch,  at  the  Royal  College  of  Chemistry,  gave 
me  confidence,  and  my  brother  and  I  entered  into  the  matter 
with  great  energy.1  At  first  we  prepared  anthracene  by  distil- 
ling pitch  ourselves,  and  thought  of  using  this  as  a  source  of  this 
hydrocarbon  on  an  extensive  scale,  as  we  felt  it  was  capable  of 
yielding  a  considerable  supply.  We  knew,  however,  that  it 
could  also  be  obtained  from  the  last  runnings  of  the  tar  stills, 
from  which  it  crystallised  on  cooling.  My  brother,  therefore, 
visited  nearly  all  the  tar  works  in  the  kingdom,  and  showed  the 
distillers  how  to  separate  the  anthracene,  promising  to  take  all 
they  could  make,  and  in  this  way  a  sufficient  and  rapidly  increas- 
ing supply  for  our  requirements  was  soon  obtained  of  all  sorts  of 
qualities,  some  being  not  much  thicker  than  pea  soup,  from  the 

1  My  father,  to  whose  great  kindness  I  was  so  much  indebted,  died  in 
1864,  so  that  our  firm  then  consisted  only  of  my  brother  and  myself. 


i8o         THE   BRITISH   COAL-TAR   INDUSTRY 

imperfect  way  in  which  it  was  drained.  Very  few  tar  distillers 
in  those  days  had  hydraulic  presses,  such  as  are  now  used,  with 
which  they  could  free  the  solid  from  the  excess  of  oil.  The 
value  of  the  anthracene  was  estimated  by  washing  with  carbon 
bisulphide,  afterwards  alcohol  was  used,  but  for  our  own  purposes 
we  all  along  used  an  anthraquinone  test.  This  method  was 
afterwards  worked  out  more  perfectly  on  the  Continent,  and  made 
a  practical  test  for  both  the  buyer  and  seller  ;  but  at  the  time  I 
am  writing  of  tar  distillers  were  not  sufficiently  educated  in  such 
matters  to  use  any  but  very  simple  tests. 

The  purification  of  the  anthracene  sufficiently  for  our  purpose 
had  then  to  be  worked  out,  and  in  doing  this  I  found  out  a 
curious  fact,  namely,  that  when  distilled  with  caustic  potash  it 
was  much  improved  in  quality — considerably  more  so  than  when 
distilled  either  alone  or  with  caustic  soda.  And  potash-distilled 
anthracene  was  especially  necessary  when  dichloranthracene  had 
to  be  prepared,  as  it  yielded  a  well-crystallised,  easily  purified 
product,  whereas  anthracene  which  had  been  distilled,  either  alone 
or  with  caustic  soda,  gave  a  badly  crystallised,  sticky  product, 
which  was  very  difficult  to  purify. 

On  examining  into  the  action  of  caustic  potash  on  anthracene, 
it  was  found  that  if,  after  the  anthracene  had  been  distilled  off, 
the  residue  was  freed  from  alkali  by  washing,  and  then  distilled, 
a  substance  very  like  anthracene  was  obtained,  which  Graebe 
subsequently  found  to  be  the  nitrogenous  compound  now  known 
as  carbazol.  It  is  by  means  of  caustic  potash  that  this  substance 
is  now  separated  from  crude  anthracene,  and  the  process  is  still 
used  to  a  large  extent  to  improve  the  quality  of  anthracene.  All 
the  anthracene  we  used  at  Greenford  Green  was  treated  in  this 
manner. 

The  purification  of  the  anthraquinone  was  at  first  effected  by 
sublimation,  followed  by  crystallisation.  A  good  deal  of  difficulty 
was  experienced  in  the  conversion  of  this  substance  into  its 
sulphonic  acid,  however,  and  at  the  high  temperature  at  which 
combination  took  place,  the  formation  of  steam  from  the  water 
produced  at  the  same  time  led  to  considerable  quantities  of  the 
anthraquinone  becoming  sublimed,  which,  although  not  lost,  yet 
was  a  source  of  trouble  in  various  ways.  The  means  of  over- 
coming this  difficulty  was  to  use  fuming  sulphuric  acid,  with 
which  anthraquinone  combined  at  a  much  lower  temperature,  but 
the  only  acid  of  the  kind  then  made  was  the  old-fashioned  Nord- 


HOFMANN    MEMORIAL  LECTURE  181 

hausen  acid.  We  imported  a  quantity  of  this,  and,  of  course, 
found  it  to  work  satisfactorily,  but  the  difficulties  and  expense 
connected  with  the  carriage  and  transport  of  this  substance  on 
account  of  its  dangerous  nature — supplied  as  it  then  was  in  large 
earthenware  bottles — made  it  unsuitable  for  use  in  this  country. 

The  artificial  alizarin  we  first  made  was  produced  by  the 
anthraquinone  process,  the  method  still  used  for  its  manufacture, 
but  the  difficulty  in  preparing  the  sulphonic  acid  in  those  early 
days  just  referred  to  caused  us  to  turn  our  attention  to  the  second 
process  I  had  discovered,  in  which  dichloranthracene  was  used. 
After  finding  out  the  best  way  of  preparing  the  substance,  our 
difficulties  in  reference  to  the  sulphonic  acid  vanished,  as  dichloran- 
thracene dissolves  easily  in  hot  ordinary  oil  of  vitriol,  producing 
dichloranthracenedisulphonic  acid  ;  on  continued  heating  this  acid 
oxidises,  hydrogen  chloride  and  sulphur  dioxide  being  evolved 
and  anthraquinonedisulphonic  acid  formed.  Without  this  process, 
the  manufacture  of  artificial  alizarin  in  this  country  could  not 
have  been  carried  on  with  much  success  in  the  early  days  of  its 
manufacture. 

The  conversion  of  the  anthraquinonesulphonic  acids  into 
colouring  matter  by  treatment  with  caustic  alkali  at  a  high 
temperature  at  first  presented  many  difficulties  when  carried  out 
on  the  large  scale.  Our  earliest  experiments  were  made  by  heat- 
ing the  mixture  in  iron  trays  in  a  large  air  bath.  Mixtures  of 
caustic  potash  and  caustic  soda  were  also  experimented  with  in- 
stead of  caustic  soda  alone.  Then  the  mixture  was  placed  in  a 
revolving  cylinder,  heated  in  an  air  bath,  small  cannon  balls  being 
put  into  the  cylinder  to  mix  the  product.  But  all  these  methods 
were  only  partially  successful,  the  percentage  of  colouring  matter 
produced  not  being  so  high  as  it  should  have  been.  At  last  heat- 
ing in  a  very  strong  iron  boiler  under  pressure  was  resorted  to, 
and  by  adopting  this  method — which  is  now  that  universally 
used — we  obtained  a  satisfactory  result. 

From  the  experiments  we  made  in  1869  we  felt  pretty  con- 
fident that  artificial  alizarin  could  be  made  at  a  price  to  compete 
with  madder  and  garancine,  and  before  the  end  of  the  year  we 
had  produced  i  ton  of  this  colouring  matter  in  the  form  of  paste, 
in  1870  40  tons,  and  in  1871  220  tons,  and  so  on  in  increasing 
quantities  year  by  year. 

The  colouring  matter  produced  from  dichloranthracene  was 
chiefly  anthrapurpurin  containing  a  little  flavopurpurin.  Theo- 


1 82         THE   BRITISH   COAL-TAR   INDUSTRY 

retically  it  should  have  consisted  of  these  products  only,  but 
owing  to  the  occurrence  of  a  secondary  action,  which  I  need  not 
refer  to  here  (see  Lectures  Soc.  Arts^  3Oth  May  1879),  ^  a^so  con~ 
tained  alizarin,  which  we  sometimes  separated  when  required  for 
dyeing  purples.  This  colouring  matter  yielded  a  shade  of  colour 
which  answered  most  of  the  requirements  of  the  consumers  for 
some  time,  as  it  was  chiefly  used  by  the  Turkey-red  dyers,  and 
the  supply  being  limited,  it  was  often  used  in  combination  with 
garancine,  as  in  this  way  more  brilliant  reds  could  be  obtained 
than  when  using  garancine  alone,  though,  of  course,  the  use  of 
the  artificial  colouring  matter  alone  yielded  still  clearer  and  more 
fiery  shades. 

Dichloranthracene  was  afterwards  found  to  yield  a  mono- 
sulphonic  acid  when  treated  with  sulphuric  acid,  provided  the 
temperature  was  kept  low  and  the  amount  of  acid  limited  ;  and 
when  oxidised  with  manganese  peroxide  or  other  oxidising  agent, 
this  yielded  anthraquinonemonosulphonic  acid,  from  which 
alizarin  alone  could  be  obtained.  But  the  properties  of  di- 
chloranthracene-monosulphonic  acid  were  such,  and  the  technical 
difficulties  of  carrying  out  the  process  so  considerable,  that  it  was 
never  used  very  successfully.  Moreover,  by  this  time,  fuming 
sulphuric  acid  had  come  into  use,  and  anthraquinonemono- 
sulphonic acid  could  be  more  readily  produced  directly  from 
anthraquinone.  As  we  had  been  successful  in  producing  artificial 
alizarin,  others  did  not  run  much  risk  in  following  our  lead  ;  yet, 
up  to  the  end  of  1870,  the  Greenford  Green  Works  were  the 
only  ones  producing  artificial  alizarin.  German  manufacturers 
then  began  to  make  it,  first  in  small  and  then  in  increasing 
quantities,  but  until  the  end  of  1873  there  was  scarcely  any  com- 
petition with  our  colouring  matter  in  this  country. 

From  the  foregoing,  it  is  seen  that,  as  in  the  case  of  the 
aniline  colours,  all  the  pioneering  work  connected  with  the 
foundation  and  establishment  of  this  branch  of  the  coal-tar  colour 
industry  was  done  in  this  country. 

For  the  due  development  of  this  industry,  it  was  necessary 
not  only  to  attend  to  technical  processes,  but  also  to  carry  on 
scientific  research  in  connection  with  it.  Early  in  1870,  I  had 
the  honour  of  bringing  before  this  Society  an  account  of  some 
experiments  on  the  formation  of  the  colouring  matter  obtained 
from  the  sulphonic  acids  of  anthraquinone,  showing  that  it 
contained  alizarin  possessed  of  both  the  chemical  and  optical 


HOFMANN    MEMORIAL   LECTURE  183 

properties  of  that  obtained  from  madder-root.  At  the  same 
time,  attention  was  directed  to  the  existence  of  a  second  colour- 
ing matter,  yielding  reds  more  scarlet  and  purples  of  a  bluer 
shade  than  alizarin  (Jour.  Chem.  Soc.,  1 870, 23,  133).  This  second 
colouring  matter  was  afterwards  made  the  subject  of  further 
investigation,  and  shown  to  be  an  isomer  of  purpurin  ;  it  was 
therefore  called  anthrapurpurin  (Jour.  Chem.  Soc.,  1872,  25,  659, 
and  1873,  26,  425).  Dichlor-  and  dibrom- anthracene  and  their 
disulphonic  acids,  etc.,  were  also  investigated.  Anthraflavic  acid, 
discovered  by  Schunck  in  some  secondary  products  sent  to  him 
from  my  works,  was  made  the  subject  of  two  researches  ;  in 
the  first  of  these,  this  compound  was  shown  to  be  an  isomer  of 
alizarin,  and  not  to  contain  C15  as  supposed  by  its  discoverer. 
In  the  second,  the  sublimed  acid  was  examined  and  found  to  be 
identical  with  the  unsublimed  ;  it  was  also  shown  that  when 
fused  with  alkali  it  did  not  yield  alizarin,  as  stated  by  Schunck, 
but  a  colouring  matter  yielding  orange-red  colours  with  alumina 
mordants.  This,  Schunck  and  Roemer,  some  time  afterwards 
showed  to  be  another  isomer  of  purpurin  which  was  named  by 
them  flavopurpurin. 

In  this  investigation,  anthraflavic  acid  was  found  to  yield  a 
diacetyl  and  dibenzoyl  derivative,  which  was  evidence  that  it  con- 
tained two  hydroxyl  groups  like  alizarin  (Jour.  Chem.  Soc.,  1873, 
26,  19).  Later  on,  an  investigation  was  made  on  the  formation 
of  anthrapurpurin,  proving  that,  as  in  the  case  of  flavopurpurin, 
the  formation  of  the  colouring  matter  from  the  disulphonic  acid 
of  anthraquinone  is  preceded  by  that  of  a  dihydroxy  derivative, 
also  an  isomer  of  alizarin,  now  known  as  isoanthraflavic  acid, 
which,  when  heated  with  caustic  alkali,  is  partially  oxidised  into 
anthrapurpurin  and  partially  reduced  (Jour.  Chem.  Soc.y  1876,1.  29, 
851).  Besides  these,  the  formation  of  bromalizarin  (Jour.  Chem. 
Soc.y  1874,  27,  401),  of  /3-nitroalizarin  (Jour.  Chem.  Soc.,  1876,  ii. 
30,  578),  of  anthrapurpuramide  (Jour.  Chem.  Soc.,  1878,  33,  216), 
and  of  the  dibromanthraquinones  discovered  by  Graebe  and  Lieber- 
mann  and  the  colouring  matters  obtainable  from  them,  were 
investigated  (Jour.  Chem.  Soc.y  1880,  37,  554).  Much  work  has 
also  been  done  in  reference  to  this  industry  by  Graebe  and 
Liebermann  and  other  investigators. 

The  manufacture  of  artificial  alizarin  in  Germany  has  been 
almost  entirely  confined  to  the  anthraquinone  process,  fuming 
sulphuric  acid  being  used  in  the  preparation  of  the  sulphonic 


1 84         THE   BRITISH   COAL-TAR   INDUSTRY 

acids.  For  this  purpose  very  strong  acid,  containing  about 
40  per  cent,  of  anhydride,  was  made  from  Nordhausen  acid, 
and  used  until  the  process  of  making  sulphuric  anhydride  by 
decomposing  sulphuric  acid  into  sulphurous  oxide,  oxygen,  and 
water,  and  recombining  the  two  former,  was  introduced. 

After  being  engaged  in  the  coal-tar  colour  industry  for 
eighteen  years,  my  connection  with  it,  technically,  came  to  an 
end  in  1874,  when  the  alizarin  industry  had  been  well  established 
and  was  rapidly  extending. 

On  looking  back  over  the  period,  it  is  of  interest  to  see  the 
wonderful  progress  the  industry  had  made  up  to  that  time — a 
progress  which  was  going  on  by  leaps  and  bounds.  I  have  no 
statistics  connected  with  the  precise  period,  but  four  years  after- 
wards, namely  in  1878 — with  the  kind  assistance  of  Dr  Caro — 
an  estimate  of  the  value  of  the  colours  produced  during  that 
year  was  obtained,  at  a  time  when  the  industry  had  just  passed 
its  majority  and  was  twenty-two  years  old.  The  sum  amounted 
to  £3,150,000.  (See  Jour.  Soc.  Arts^  3Oth  May  1879.)  Of  its 
present  position,  it  is  very  difficult  to  speak.  Certainly  its  pro- 
gress has  been  very  great  since  1878  ;  but  chiefly  owing  to  the 
scientific  skill  bestowed  upon  the  production  of  the  colouring 
matters,  their  cost  has  been  greatly  dimished,  so  that  I  under- 
stand rosaniline  hydrochloride,  which  once  was  worth  about 
£3,  35.  per  ounce,  may  now  be  purchased  at  2s.  9d.  per  lb.,  and 
aniline  at  less  than  6d.  per  lb.  .  .  . 

During  the  early  days  of  the  coal-tar  colour  industry,  the 
complaint  was  made  that  the  prosecution  of  purely  scientific 
chemistry  was  being  injured  by  its  influence,  as  chemists  were 
everywhere  experimenting  with  aniline  and  other  products,  with 
objects  of  a  more  selfish  than  scientific  character.  It  is  probable 
that  there  was  some  truth  in  this  for  a  time,  but  it  was  not  long 
before  a  welcome  change  set  in,  and  the  work  carried  on  in 
relation  to  this  industry  was  soon  conducted  in  a  scientific  spirit, 
even  when  the  result  sought  for  was  expected  to  be  of  technical, 
as  well  as  where  it  was  expected  to  be  of  scientific,  value.  But 
the  amount  of  work  carried  on  from  the  latter  point  of  view 
increased  more  and  more,  as  interesting  questions  connected  with 
the  colouring  matters  and  the  methods  by  which  they  were  pro- 
duced presented  themselves  to  chemists,  and  now  if  we  look 
back  and  consider  what  has  been  accomplished,  we  find  that 
this  industry  has  directly  and  indirectly  had  a  most  marvellous 


HOFMANN   MEMORIAL   LECTURE  185 

influence  on  the  advancement  of  chemical  science,  especially  that 
part  of  it  relating  to  the  aromatic  series  of  compounds.  No 
other  industry  in  existence  can  at  all  be  compared  with  it  from 
this  point  of  view.  This  has  arisen  from  a  variety  of  circum- 
stances, one  of  which  is  that  it  has  not  been  carried  on  by  the 
rule-of-thumb  method  which  has  been  so  common  in  other  cases. 
Again,  as  it  has  utilised  the  discoveries  of  chemists,  it  has 
handed  back  to  them  in  return  new  products  which  they  could 
not  have  obtained  without  its  aid,  and  these  have  served  as 
materials  for  still  more  advanced  work  :  this  kind  of  exchange, 
indeed,  has  been  going  on  so  repeatedly,  that  products  formerly 
of  the  rarest  and  most  complex  character  are  now  quite  common 
substances  in  the  coal-tar  colour  works. 

We  knew  that  aniline  was  at  first  a  rare  substance,  and  when 
it  was  afterwards  proposed  to  use  ethyl  and  methyl  iodides  in 
the  preparation  of  ordinary  dyestuffs,  it  seemed  incredible  that 
such  substances  could  be  introduced  for  such  a  purpose  as 
already  mentioned,  substances  which  were  but  rarely  met  with 
even  in  chemical  laboratories  :  but  what  are  these  compared  with 
the  substances  now  in  use  ? — their  names  would  be  too  numerous 
to  mention.  One  of  the  most  striking  facts  connected  with  this 
industry  is  the  remarkably  rapid  way  in  which  it  has  utilised 
new  discoveries  which  have  often  been  no  sooner  made  than  they 
have  been  practically  applied.  This  do  doubt  arises  from  the 
fact  that  an  ever-increasing  army  of  highly  trained  and  highly 
gifted  chemists  are  engaged  in  the  industry,  especially  on  the 
Continent,  provided  with  splendid  laboratories,  libraries  of 
scientific  works,  and  all  the  most  advanced  appliances  required 
in  scientific  research  ;  and  the  members  of  this  army  are  not 
only  making  discoveries  themselves  and  applying  them,  but  are 
always  on  the  alert  to  make  the  discoveries  of  others  subservient 
to  the  industry. 

As  I  have  already  mentioned,  when  this  industry  was  first 
instituted,  organic  chemistry  was  comparatively  in  its  infancy, 
especially  if  we  regard  it  from  our  present  standpoint.  Kekul£ 
had  not  then  brought  forward  his  remarkable  benzene  theory, 
and  after  he  had  done  so  its  bearings  required  much  elucidation 
before  their  importance  was  well  understood.  Only  solid  tolui- 
dine  was  known,  orthotoluidine  not  having  been  discovered, 
although  it  was  constantly  present  in  the  high  boiling  aniline 
used  in  making  rosaniline  ;  but  now  the  facts  connected  with 


1 86         THE   BRITISH   COAL-TAR   INDUSTRY 

the  ortho-,  meta-,  and  para-position  in  substances  containing  the 
benzene  nucleus,  or  of  the  a-  and  ^-positions  in  the  naphthalene 
series,  are  among  the  most  important  to  be  considered  in  the 
manufacture  of  colouring  matters  ;  in  fact,  this  industry  has  done 
more  to  accentuate  the  importance  and  character  of  these  positions 
than  any  other  kind  of  experimental  work. 

Although  at  the  commencement  of  the  industry  a  good  deal 
of  work  of  a  purely  experimental  character  had  to  be  done, 
nevertheless,  from  the  first  it  was  carried  out  on  scientific  lines, 
and  this  characteristic  increased  very  rapidly,  as  is  seen  by  the 
early  date  at  which  mauve  and  magenta  were  obtained  in  the 
pure  crystallised  condition  :  it  was  at  this  period,  as  previously 
stated,  that  Hofmann  commenced  his  researches  on  rosaniline 
and  its  derivatives,  and  on  other  colouring  matters,  and  these 
researches,  taken  with  those  of  others,  bear  out  the  observations 
which  have  just  been  made.  In  looking  over  the  work  of 
Hofmann  in  this  field,  all  who  have  had  experience  in  the  investi- 
gation of  the  subjects  he  undertook  must  realise  that  they  pre- 
sented no  ordinary  difficulties,  especially  as  for  some  time  he 
had  nothing  to  guide  him  in  his  conclusions  but  the  analytical 
results.  In  the  early  days  of  organic  chemistry,  it  is  well  known 
that  on  finding  colouring  matters  in  the  products  they  were 
examining,  chemists  usually  regarded  them  as  impurities,  and 
the  use  of  animal  charcoal  and  other  means  were  resorted  to  for 
the  purpose  of  getting  rid  of  them  ;  and  those  who  undertook 
to  do  the  examination  of  colouring  matters  themselves  were 
considered  as  bold  men,  and  not  likely  to  get  much  result  from 
their  labour.  Doubtless,  there  was  much  truth  in  this.  Hof- 
mann, however,  was  a  bold  man,  and  not  one  to  be  daunted,  but 
rather  inspired,  by  difficulties  ;  and  from  his  results  we  see  how 
great  his  success  was  in  this  department  of  chemistry,  some  of 
his  work  proving  to  be  of  direct  practical  value,  whilst  other 
parts  possessed  important  bearings  both  on  the  practical  and 
scientific  development  of  this  subject.  His  researches  on  colour- 
ing matters  extended  over  a  quarter  of  a  century,  commencing 
in  1862  with  rosaniline,  and  ending  in  1887  with  quinoline  red  ; 
and  during  that  period  there  were  but  few  years  in  which  he  did 
not  produce  one  or  more  investigations,  either  related  to  colour- 
ing matters  or  the  products  connected  with  their  production. 

It  will  be  obvious  from  what  has  been  said,  how  Hofmann 's 
early  work  —  after  that  of  Faraday,  Unverdorben,  Runge, 


HOFMANN   MEMORIAL  LECTURE  187 

Fritsche,  Mitscherlich,  and  Zinin — continued  to  pave  the  way 
for  the  introduction  of  the  coal-tar  colour  industry,  also  how  the 
important  influence  he  exercised  on  the  training  of  his  students 
led  in  the  same  direction.  I  especially  refer  to  Mansfield,  who 
did  such  valuable  work  on  coal-tar,  and  Nicholson,  whose  chemi- 
cal education  under  Hofmann  was  such  an  important  preparation 
for  the  work  he  undertook  in  after  years  on  rosaniline  and  its 
derivatives  ;  and  if  I  may  speak  for  myself,  I  can  only  say  how 
much  I  owe  to  Hofmann's  training,  which  fitted  me  to  carry  out 
the  work  which  fell  to  my  lot  in  connection  with  the  introduction 
and  development  of  this  industry.  Then  if  we  further  consider 
the  importance  of  the  beautiful  researches  Hofmann  made,  some 
of  which  yielded  practical  results,  throwing  fresh  light  on  the 
nature  of  the  colouring  matters  and  products  related  to  them 
which  were  obtained  as  time  went  on,  some  idea  may  be  formed 
of  the  contributions  made  by  Hofmann  and  his  school  to  the 
coal-tar  colour  industry. 

And  yet  we  must  bear  in  mind  that  his  work  in  this  depart- 
ment of  chemistry  represents  but  a  small  part  of  all  that  he 
accomplished — indeed,  the  amount  of  scientific  work  he  did  was 
something  marvellous. 


X.:    igoi 
THE   SYNTHESIS   OF   INDIGO 

BY    PROFESSOR    R.    MELDOLA,    F.R.S.,    F.I.C. 

(Journal  of  the  Society  of  Arts^  1901,  p.  397) 

THIS  paper  discusses  the  various  synthetical  processes  which  have  been 
used  for  the  production  of  indigo.  The  latter  portion  of  the  paper  is 
quoted  in  the  article  on  "  The  Indigo  Crisis  " :  see  p.  219. 


188 


XL:    1901 

THE  RELATIVE  PROGRESS 

OF  THE  COAL-TAR  COLOUR  INDUSTRY  IN 

ENGLAND    AND    GERMANY    DURING    THE 

PAST  FIFTEEN  YEARS 

BY  ARTHUR  G.  GREEN,  F.I.C.,  F.C.S. 
(Paper  read  before  the  British  Association,  Section  B,  Glasgow,  1901) 

THE  coal-tar  colour  manufacture  has  well  been  called  the  flower 
of  the  chemical  industries.  Although  in  absolute  money  value  of 
its  products  not  equalling  some  other  branches  of  industrial 
chemistry,  it  represents  the  highest  development  of  applied 
chemical  research  and  chemical  engineering,  and  may  well  be 
taken  as  the  pulse  of  the  whole  chemical  trade.  Indeed,  a 
country  which  allows  the  most  scientific  branch  of  chemical 
industry  to  languish  cannot  expect  to  maintain  pre-eminence  for 
long  in  any  simpler  branch  of  chemical  manufacture  ;  since  the 
skill  trained  for  attacking  the  difficult  problems  of  organic 
chemistry  is  certain  sooner  or  later  to  be  brought  to  bear  on  the 
simpler  questions  presented  in  the  manufacture  of  so-called 
"  heavy  "  chemicals  (acids,  alkalies,  bleach,  salts,  etc.),  and  processes 
hitherto  often  left  to  the  supervision  of  foremen  will  be  taken  in 
hand  by  educated  chemists,  with  consequent  improvement  in 
methods  of  manufacture,  better  yields,  purer  products,  and  cheaper 
production.  The  importance  of  the  coal-tar  industry  cannot 
therefore  be  estimated  alone  by  the  value  of  its  products,  for  it 
exerts  a  widespread  effect  upon  all  other  branches  of  chemical  manu- 
facture, from  many  of  which  it  draws  its  supplies  of  raw  material. 
As  a  pregnant  example  of  this  influence,  especially  noticeable  during 
the  last  decade,  I  may  mention  the  revolution  which  is  taking 

189 


1 90         THE   BRITISH   COAL-TAR   INDUSTRY 

place  in  the  manufacture  of  sulphuric  acid,  that  most  important 
product  of  the  "  heavy  "  chemical  trade.  A  strong  demand  had 
arisen  in  the  colour  industry  for  a  large  and  cheap  supply  of 
sulphuric  anhydride,  chiefly  in  connection  with  the  manufacture 
of  alizarin  colours  and  of  artificial  indigo.  With  the  object  of 
satisfying  their  own  requirements  in  this  respect,  the  Baden 
Aniline  and  Soda  Works  of  Ludwigshafen  devoted  much  time 
and  research  to  the  problem  of  improving  the  catalytic  process 
usually  known  by  the  name  of  Winckler,  a  modification  of  which 
process  had  been  worked  in  this  country  by  Squire  Chapman  and 
Messel  since  1876.  This  endeavour  was  attended  with  such 
success  that  by  means  of  the  process  and  plant  which  they  finally 
evolved  they  were  enabled  to  produce  sulphuric  anhydride  so 
cheaply  that  not  only  could  it  be  used  as  such  for  a  large  variety 
of  purposes,  but  by  combination  with  water  afforded  a  profitable 
source  of  sulphuric  acid.  This  new  method  of  manufacturing 
sulphuric  acid  is,  for  concentrated  acid  at  least,  cheaper  than  the 
chamber  process  ;  and  since  the  product  is  absolutely  free  from 
arsenic,  and  can  be  produced  at  any  desired  concentration,  it 
seems  likely  to  supplant  eventually  the  time-honoured  method 
of  manufacture. 

Besides  exerting  this  influence  upon  the  inorganic  chemical 
manufactures,  the  coal-tar  industry  has  given  birth  during  recent 
years  to  several  important  daughter  industries.  The  manufacture 
of  synthetic  medicinal  agents,  artificial  perfumes,  sweetening 
materials,  antitoxines,  nutritives,  and  photographic  developers 
are  all  outgrowths  of  the  coal-tar  industry,  and  in  great  part  still 
remain  attached  to  the  colour  works  where  they  originated.  Of 
these  subsidiary  industries  the  most  important  is  the  manufacture 
of  synthetic  medicinal  preparations,  which  has  already  attained  to 
large  proportions,  and  bids  fair  to  revolutionise  medical  science. 
The  requirements  of  the  coal-tar  industry  have  further  led  to 
great  advances  in  the  design  and  production  of  chemical  plant, 
such  as  filter-presses,  autoclaves,  fractionating  columns,  vacuum 
pumps  and  stills,  suction  filters,  enamelled  iron,  aluminium,  and 
stoneware  vessels,  etc.,  for  the  supply  of  which  extensive  works 
have  become  necessary. 

It  is  a  frequently  quoted  remark  of  the  late  Lord  Beacons- 
field  that  the  chemical  trade  of  a  country  is  a  barometer  of  its 
prosperity,  and  the  chemical  trade  of  this  country  has  always 
been  regarded  as  a  most  important  branch  of  our  manufactures. 


PROGRESS  DURING  FIFTEEN  YEARS  1886-1900    191 

Even  those  who  might  be  inclined  to  regard  our  declining 
position  in  the  colour  industry  with  more  or  less  indifference 
would  consider  the  loss  of  a  material  portion  of  our  general 
chemical  trade  as  nothing  less  than  a  national  calamity.  As 
already  pointed  out,  however,  the  two  are  indissolubly  con- 
nected, the  coal-tar  industry  being  an  essential  and  inseparable 
part  of  the  chemical  industry  as  a  whole.  It  is  with  the  object 
of  ascertaining  our  present  and  future  prospects  in  the  chemical 
trade  of  the  world  that  1  propose  to  compare  the  relative  develop- 
ment of  the  colour  industry  in  England  and  Germany  during  the 
past  fifteen  years.  It  was  at  the  commencement  of  this  period, 
that  is  to  say  in  the  year  1886,  that  Professor  Meldola,  in  a  paper 
read  before  the  Society  of  Arts,  gave  such  a  masterly  account  of 
the  position  of  the  industry  of  this  country  at  that  date,  and 
sounded  a  warning  note  to  our  manufacturers  and  business  men 
regarding  its  future  progress. 

If  an  excuse  is  required  for  my  venturing  to  refer  again  to  a 
subject  upon  which  so  much  has  been  said  and  written  already, 
it  is  supplied  by  the  fact  that  the  warnings  repeatedly  given  by 
those  who  saw  the  future  clearly  (notably  by  Professors  Meldola 
and  Armstrong)  have  remained  largely  unheeded  by  our  business 
men.  The  conclusions  which  are  forced  upon  us  are  unfortun- 
ately not  of  a  reassuring  nature  for  our  national  trade,  but  it  is 
well  to  remember  that  nothing  is  gained  by  burying  our  heads 
in  the  sand,  and  that  the  cure  of  a  disease  can  only  be  effected 
after  an  accurate  diagnosis  of  its  cause. 

The  period  which  we  have  to  consider  has  been  one  of 
extraordinary  activity  and  remarkable  development  in  the  coal-tar 
industry,  and  before  I  pass  to  the  economic  aspect  of  the  question 
I  shall  ask  you  to  consider  very  superficially  some  of  the  main 
points  in  this  advance.  In  no  other  industry  than  this  have  such 
extraordinarily  rapid  changes  and  gigantic  developments  taken 
place  in  so  short  a  period,  developments  in  which  the  scientific 
elucidation  of  abstract  problems  has  gone  hand  in  hand  with 
inventive  capacity,  manufacturing  skill,  and  commercial  enterprise. 
In  no  other  industry  has  the  close  and  intimate  interrelation  of 
science  and  practice  been  more  clearly  demonstrated. 

Born  in  1856,  the  colour  industry  had  already  attained  to  a 
considerable  state  of  development  by  the  year  1886.  The  period 
prior  to  this  might  well  be  called  the  "  rosaniline  period,"  since 
it  is  chiefly  marked  by  the  discovery  and  development  of  colour- 


192         THE   BRITISH   COAL-TAR   INDUSTRY 

ing  matters  of  the  rosaniline  or  triphenylmethane  group,  such 
as  magenta,  aniline  blue,  Hofmann  violet,  methyl  violet,  acid 
magenta,  acid  violets,  phosphine,  Victoria  blues,  auramine, 
malachite  green,  and  acid  greens.  Individual  members  of  other 
groups  had  already  been  discovered,  but  the  latter  had  not 
yet  attained  to  the  importance  which  they  were  destined  later 
to  occupy.  This  is  especially  the  case  with  the  class  of  colouring 
matters  containing  the  double  nitrogen  radical  known  as  "  azo  " 
colours.  This  group  of  compounds  has,  during  the  fifteen  years 
which  we  have  to  consider,  attained  to  such  enormous  dimensions 
and  importance  that  this  interval  may  fairly  be  termed  the 
"  azo  period."  The  number  of  individual  compounds  belonging 
to  this  class,  which  have  either  been  prepared  or  are  at  present 
preparable,  runs  into  many  millions  and  far  exceeds  the  members 
of  all  other  groups  of  colouring  matters  put  together.  In 
commercial  importance  also  they  occupy  a  position  at  present  far 
in  advance  of  any  other  group,  the  employment  of  some  of  them 
(e.g.  the  "  azo "  blacks)  amounting  to  many  thousands  of  tons 
annually.  A  great  stimulus  to  the  investigation  of  the  azo 
compounds  was  given  by  the  discovery  by  Bottiger  in  1884  of 
the  first  colour  possessing  a  direct  affinity  for  cotton  (Congo  red), 
which  was  followed  within  a  few  years  by  a  rapidly  increasing 
series  of  colours  of  all  shades  having  similar  dyeing  properties. 
The  azo  colours  known  prior  to  this  time  were  either  basic 
colours  (aniline  yellow,  chrysoidine,  Bismarck  brown,  etc.)  or 
acid  wool  colours  (xylidine  scarlet,  croceine  scarlet,  etc.).  The 
great  simplification  of  cotton  dyeing  brought  about  by  the 
introduction  of  the  new  group  of  azo  colours — "  benzo "  or 
"  diamine  "  colours  as  they  were  called — led  to  a  rapid  increase 
in  their  number,  and  compounds  containing  two,  three,  four,  or 
more  double-nitrogen  groups,  linking  together  the  residues  of 
various  paradiamines  (benzidine,  tolidine,  dianisidine,  azoxy- 
toluidine,  paraphenylenediamine,  naphthylenediamine,  etc.)  to 
various  naphthol-,  amidonaphthol-,  and  naphthylamine  sulphonic 
acids  made  their  appearance  in  quick  succession.  Simultaneously 
therewith  proceeded  the  discovery  and  investigation  of  the 
various  isomeric  derivatives  of  naphthalene  required  as  raw 
products  for  the  preparation  of  these  colours,  an  investigation 
which  was  largely  aided  by  the  classical  research  on  the  isomerism 
of  naphthalene  compounds  carried  out  in  this  country  by  Arm- 
strong and  Wynne. 


PROGRESS  DURING  FIFTEEN  YEARS  1886-1900    193 

Another  method  of  applying  azo  colours  to  cotton,  by  which 
much  faster  shades  are  obtained,  was  introduced  by  Messrs 
Read  Holliday,  of  Huddersfield,  in  1880,  and  consisted  in 
producing  unsulphonated  azo  compounds  on  the  fibre  by  direct 
combination.  Owing  to  the  technical  difficulties  which  were  at 
first  encountered  in  applying  this  process  it  has  only  reached 
its  full  development  during  the  last  few  years  and  at  other  hands 
than  those  of  its  discoverers.  The  most  important  colour 
produced  by  this  method  is  paranitraniline  red,  for  which  over 
two  hundred  tons  of  chemically  pure  paranitraniline  are  manu- 
factured annually. 

The  search  for  direct  cotton  colours  led  the  author  in  1887 
to  the  discovery  of  primuline.  This  compound,  having  a  direct 
affinity  for  cotton  and  containing  at  the  same  time  a  diazotisable 
amido  group,  could  be  used  for  the  synthesis  of  various  azo 
colours  on  the  fibre  which  were  remarkable  for  great  fastness  to 
washing.  It  has  had  a  large  employment  for  the  production 
of  fast  reds,  and  the  new  principle  of  dyeing  which  it  introduced 
has  been  considerably  extended  in  other  so-called  "  diazo  "  colours. 
The  closer  investigation  of  the  thiazol  group,  to  which  primuline 
belongs,  further  led  to  the  discovery  of  many  other  cotton 
colours  belonging  to  this  family,  amongst  the  most  important 
of  which  are  the  brilliant  greenish-yellow  called  turmerine  or 
Clayton  yellow,  the  light-fast  chlorophenine  or  chloramine  yellow, 
the  pure  greenish  basic  yellow  thioflavine,  and  the  fast  cotton 
pink  erica. 

Passing  over  the  stilbene  azo  colours  and  the  basic  azo 
ammonium  or  Janus  colours,  there  remains  a  class  of  azo  com- 
pounds to  which  1  must  shortly  refer,  namely,  the  mordant 
azo  colours,  which  with  the  growing  demand  for  faster  shades 
have  recently  come  into  much  prominence.  In  these  compounds 
the  presence  of  an  orthohydroxyl  or  carboxyl  group  gives  to 
the  colour  the  property  (following  Liebermann  and  v.  Kosta- 
necki's  rule)  of  combining  with  metallic  mordants,  especially 
chromium  oxide,  and  producing  therewith  insoluble  and  fast 
lakes  on  the  wool  or  cotton  fibre. 

We  now  come  to  the  consideration  of  three  analogously 
constituted  groups  of  colouring  matters,  namely,  the  azines, 
oxazines,  and  thiazines.  The  laborious  scientific  investiga- 
tions of  Fischer  and  Hepp,  Bernthsen,  Kehrmann,  and  others 
on  the  constitution  of  these  groups  of  compounds,  the  first 

13 


194         THE   BRITISH   COAL-TAR   INDUSTRY 

members  of  which  (methylene  blue,  safranine,  and  Meldola's 
blue)  were  discovered  in  a  very  early  stage  of  the  industry 
when  little  or  nothing  was  known  of  their  structure,  combined 
with  the  theoretical  views  on  the  quinonoid  structure  of  such 
colouring  matters  promulgated  by  Armstrong  and  adopted 
by  Nietzki,  led  to  the  discovery  of  many  valuable  new  mem- 
bers of  these  classes.  Amongst  the  latter  may  be  specially 
mentioned  the  rosindulines,  indoine  blue,  induline  scarlet,  rhodu- 
lines,  etc. 

Passing  to  the  pyrone  and  acridine  groups  in  which  much 
investigation  has  also  been  conducted,  the  most  notable  advances 
have  been  the  discovery  of  the  rhodamines,  a  class  of  pure 
basic  reds,  and  of  the  basic  yellows  and  oranges  allied  tc 
phosphine,  namely,  acridine  yellow,  benzoflavine,  and  acridine 
orange. 

It  is  in  the  alizarin  group  next  to  the  azo  group  that  the 
greatest  progress  must  be  recorded.  The  demand  for  fasl 
colours  for  calico  printing  and  for  dyeing  chrome-mordantec 
wool  to  withstand  severe  "  milling "  operations  has  led  to  c 
long  series  of  investigations  and  patents  for  producing  nev^ 
derivatives  of  anthraquinone.  These  new  products,  known  ir 
commerce  as  alizarin  Bordeaux,  alizarin  cyanines,  anthracene 
blues,  alizarin  viridine,  alizarin  saphirol,  etc.,  are  polyoxy-  01 
amido-oxyanthraquinones,  for  the  preparation  of  which  eithei 
alizarin  or  nitroanthraquinones  are  the  usual  starting-points. 

Passing  over  some  smaller  groups,  we  now  come  to  a  ver) 
peculiar  class  of  dyestuffs  containing  sulphur,  which  although 
discovered  by  Croissant  and  Brettoniere  in  1873,  remainec 
confined  to  a  single  representative — Cachou  de  Laval, — unti 
Raymond  Vidal  in  1893  obtained  a  very  fast  black  colouring 
matter,  which  dyed  unmordanted  cotton,  by  heating  para-amido 
phenol  with  sulphur  and  sodium  sulphide.  The  possibility  o 
replacing  aniline  black  in  cotton  dyeing  by  a  direct  colouring 
matter,  and  possibly  also  of  obtaining  other  shades  which,  thougl 
dyed  in  a  single  bath,  would  resist  subsequent  "  cross  dyeing ' 
of  the  wool  in  mixed  fabrics,  lent  an  immense  impulse  to  th< 
study  of  this  class  of  colouring  matters ;  and  although  thei 
molecular  structure  still  remains  wrapped  in  obscurity,  man] 
new  representatives  have  followed  each  other  in  rapid  succession 
ranging  in  shade  from  blacks  of  various  hues  to  browns,  olives 
greens,  and  blues.  As  the  most  important  of  these  I 


PROGRESS  DURING  FIFTEEN  YEARS  1886-1900    195 

mention  Vidal  black,  immedial  black,  katigene  black,  immedial 
blues,  pyrogene  blues,  katigene  brown,  katigene  green,  etc. 

It  may  fairly  be  claimed,  however,  that  the  greatest  triumph 
of  the  coal-tar  industry  for  the  past  fifteen  years  has  been  the 
successful  production  of  artificial  indigo  on  a  large  manufacturing 
scale. 

Returning  from  the  scientific  to  the  economic  aspect  of  the 
subject,  I  shall  ask  you  now  to  consider  what  share  we  have 
obtained  in  the  great  expansion  of  trade  resulting  from  all  these 
new  discoveries,  many  of  which  have  originated  in  this  country. 
The  development  of  the  industry  in  Germany  is  well  illustrated 
by  the  following  figures  : — 

EXPORTS  FROM  GERMANY  TO  THE  WORLD 


1885. 

1895. 

1899. 

Tons. 

Tons. 

Tons. 

Aniline  oil  and  salt  .... 
Coal-tar  colours  (excl.  alizarin)  . 
Alizarin  colours        .... 

1713 
4646 
4284 

7,135 
15^89 
8,927 

!7>639 

Again,  if  we  take  values,  we  find  that  total  exports  of  coal- 
tar  colours  from  Germany  amounted  in  1894  to  £2,600,000, 
and  in  1898  to  £3,500,000,  an  increase  of  nearly  a  million  in 
four  years.  The  latter  figure  is  practically  the  same  as  that 
given  by  Per  kin  as  an  estimate  of  the  world's  total  production  in 
1885,  showing  how  great  the  increase  has  been  since  this  date. 

The  value  of  Germany's  entire  production  is  somewhat 
difficult  to  arrive  at.  Witt,  in  his  report  on  the  German  chemical 
exhibit  at  the  Paris  Exhibition,  gives  as  the  value  of  the  total 
chemical  industry  of  Germany  for  the  year  1897  the  enormous 
sum  of  46^-  million  pounds  sterling.  Of  this  sum  Lef&vre 
estimates  that  at  least  one-tenth  may  be  put  down  to  colouring 
matters,  and  another  tenth  to  raw,  intermediate,  and  synthetic 
products  from  coal  tar  other  than  colours,  and  he  thus  assigns 
for  the  total  annual  value  of  the  coal-tar  industry  of  Germany 
the  sum  of  nine  to  ten  million  pounds  sterling.  With  the 
increase  in  the  production  of  synthetic  indigo,  it  may  be  taken 
to-day  to  considerably  exceed  this  figure. 


196         THE   BRITISH   COAL-TAR   INDUSTRY 

One  may  well  wonder  what  becomes  of  this  enormou: 
quantity  of  coal-tar  products.  According  to  the  United  State; 
consular  reports  the  3^  million  pounds'  worth  of  coal-tar  colour; 
exported  by  Germany  in  1898  were  consumed  as  follows  : — 

The  United  States  took      ....  .£750,000  worth 
The  United  Kingdom  took         .         .         .         730,000      „ 
Austria  and  Hungary      „            ...         350,000      „ 
Italy                                   „            .         .  225,000      „ 

China  ,,  ...         270,000      „ 

whilst  the  rest  of  the  world  took  the  remainder. 

The  great  increase  in  production  in  Germany  is  furthe 
shown  by  the  growth  in  the  capital  and  number  of  workpeopL 
employed.  Thus  according  to  a  report  of  the  Badische  Works 
recently  issued,  the  capital  of  this  company,  which  was  increasec 
in  1889  from  £900,000  to  £1,050,000,  will  be  further  augmente( 
this  year  by  the  issue  of  £750,000  of  debentures.  The  numbe 
of  workpeople  employed  by  this  company  in  1900  was  6485,  a 
against  4800  in  1896,  an  increase  of  over  33  per  cent,  in  fou 
years.  The  firm  of  Leopold  Cassella  &  Co.,  of  Mainkur,  nea 
Frankfurt,  have  increased  the  number  of  their  workpeople  fron 
545  in  1890  to  1800  in  1900. 

Passing  now  to  England,  we  find  that  the  imports  of  coal-ta 
colours  into  the  country  are  steadily  rising,  as  is  shown  by  th 
following  figures  taken  from  the  Board  of  Trade  returns  : — 


IMPORTS  OF  COAL-TAR  DYESTUFFS  INTO  ENGLAND  DURING  THE  LAST 
FIFTEEN  YEARS  (EXCLUDING  INDIGO) 


1886 
1887 
1888 
1889 
1890 


542,000 
569,000 
609,200 
594,400 


1891  . 

1892  .    .  542,200 

1893  .    .  504,000 

1894  .    .  599,000 

.  710,000 


1896  . 

1897  .  .  695,40 

1898  .  .  739,00 

1899  .  .  708,80 

1900  .  .  720,00 


Contrasted  with  this,  the  exports  of  coal-tar  colours  manu 
factured  in  'England  have  fallen  from  £530,000  in  1890  t< 
£366,500  in  1899.  Comparing  these  figures  with  the  rapidl; 
increasing  export  trade  of  Germany,  it  is  seen  that  wherea 
formerly  the  English  export  trade  in  artificial  colours  was  abou 
one-quarter  that  of  Germany,  it  does  not  now  amount  to  a  tenti 
part.  It  is  therefore  only  too  apparent  that  we  have  had  bu 
little  share  in  the  great  increase  which  this  industry  has  experi 


PROGRESS  DURING  FIFTEEN  YEARS  1886-1900    197 

enced  during  the  past  fifteen  years,  and  that  we  have  not  even 
been  able  to  supply  the  expansion  in  our  own  requirements.  In 
order  to  ascertain  what  proportion  of  our  own  needs  we  at  present 
furnish,  I  am  able  to  lay  before  you  the  following  interesting 
figures,  which  have  been  kindly  supplied  to  me  by  the  Bradford 
Dyers1  Association  and  the  British  Cotton  and  Wool  Dyers' 
Association,  who  together  form  a  large  proportion  of  the  entire 
dyeing  trade  : — 

COLOURING  MATTERS  USED  BY  BRADFORD  DYERS' 
ASSOCIATION 

English,  10  per  cent. ;  German,  80  per  cent.  ;  Swiss,  6  per 
cent. ;  French,  4  per  cent. 

COLOURING  MATTERS  USED  BY  BRITISH  COTTON  AND  WOOL 
DYERS'  ASSOCIATION 

Aniline  Colours. — English,  22  per  cent.  ;  foreign,  78  per 
cent. 

Alizarin  Colours. — English,  1-65  per  cent.  ;  foreign,  98*35 
per  cent. 

The  English  Sewing  Cotton  Company  have  also  very  kindly 
supplied  me  with  a  detailed  analysis  of  their  consumption,  from 
which  it  appears  that  out  of  a  total  of  sixty  tons  of  colouring 
matters  and  other  dyeing  materials  derived  from  coal  tar  only 
9  per  cent,  were  of  English  manufacture. 

The  following  table  of  statistics  of  the  six  largest  German 
firms  gives  a  fair  picture  of  the  present  dimensions  of  the 
industry  in  that  country. 

The  joint  capital  of  these  six  firms  amounts  to  at  least 
i\  millions.  They  employ  together  about  500  chemists,  350 
engineers  and  other  technologists,  1360  business  managers, 
clerks,  travellers,  etc.,  and  over  18,000  workpeople.  Compared 
with  such  figures  as  these  the  English  colour  manufacture 
assumes  insignificant  proportions.  The  total  capital  invested 
in  the  coal-tar  colour  trade  in  England  probably  does  not  exceed 
£500,000,  the  total  number  of  chemists  employed  cannot  be 
more  than  thirty  or  forty,  and  the  number  of  workmen  engaged 
in  the  manufacture  does  not  amount  to  over  a  thousand. 


198         THE   BRITISH   COAL-TAR   INDUSTRY 

POSITION  OF  THE  Six  LARGEST  COLOUR  WORKS  IN  GERMANY  IN  YEAR  1900 


— 

Badische 
Aniline 
Works. 

Meister, 
Lucius  & 
Bruning. 

Farben- 
fabriken 
Bayer 
&Co. 

Berlin 
Aniline 
Co. 

Cassella 
&Co. 

Farbwerk 
Mlihlheim, 
Leonhardt 
&Co. 

Total  of 
six  largest 
firms. 

Capital 

.£1,050,000 

£833,000 

£882,000 

£441,000 

Private 

£157,000 

About 

concern 

^2,500,001 

Number      of 

148 

120 

145 

55 

N 

About  5oc 

chemists 

Number      of 

75 

36 

175 

3i 

About  35C 

engineers, 

60 

dyers,    and 

other   tech- 

•   45° 

nologists 

^ 

Commercial 

305 

211 

5oo 

150 

170 

About  136 

staff 

Workpeople 

6485 

3555 

4200 

1800 

1800 

' 

About  1  8,  2 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Per  cent. 

Dividends  in 

24 

26 

18 

I2J 

Not 

9 

— 

1897 

known 

Dividends  in 

5  } 

>  j 

ii 

15 

j  » 

3 

— 

1898 

Dividends  in 

» 

»> 

» 

ii 

ii 

5 

— 

1899 

Dividends  in 

» 

20 

» 

? 

>  > 

Nil 

— 

1900 

A  similar  relative  proportion  is  maintained  in  the  number  o 
patents  for  new  colouring  matters  and  other  coal-tar  product 
taken  by  the  English  and  German  firms,  as  is  shown  by  th 
following  table  : — 

COMPARISON  OF  NUMBER  OF  COMPLETED  ENGLISH  PATENTS  FOR  COAI 
TAR  PRODUCTS  TAKEN  DURING  1886-1900  BY  Six  LARGEST  ENGLIS: 
AND  Six  LARGEST  GERMAN  FIRMS 


German  Firms 

Badische  Aniline  Works  .  .  179 
Meister,  Lucius  &  Briining  .  231 
Farbfabriken  Bayer  &  Co.  .  306 
Berlin  Aniline  Co.  .  .  .119 
L.  Cassella  &  Co.  .  .  -75 
Farbwerk  Miihlheim,  Leonhardt 
&  Co 38 


English  Firms 

Brooke,  Simpson  &  Spiller 

Clayton  Aniline  Co.  . 

Levinstein         . 

Read  Holliday  &  Co. 

Claus  &  Ree     . 

W.  G.  Thompson       . 


To tal  of  six  German  firms  .     948  Total  of  six  English  firms     .     8 

Nor  does  the  potential  loss  which  we  have  sustained  by  ou 
inability  to  take  advantage  of  a  growing  industry  represent  th 


PROGRESS  DURING  FIFTEEN  YEARS  1886-1900    199 

sum  total  of  our  losses.  The  new  colouring  matters,  made 
almost  exclusively  in  Germany,  have  in  many  cases  been  intro- 
duced as  substitutes  for  natural  products,  which  were  staple 
articles  of  English  commerce.  Madder  and  cochineal  have  been 
replaced  by  alizarin  and  azo  scarlets,  the  employment  of  many 
dyewoods  has  greatly  decreased,  whilst  at  the  present  moment 
logwood  and  indigo  are  seriously  threatened.  Regarding  the 
indigo  question,  so  much  has  been  written  that  I  do  not  propose 
to  occupy  space  in  its  further  discussion,  but  will  only  point  out 
that  the  complete  capture  of  the  indigo  market  by  the  synthetic 
product,  which  would  mean  a  loss  to  our  Indian  dependencies  of 
£3,000,000  a  year,  is  regarded  by  the  Badische  Company  as  so 
absolutely  certain  that,  having  already  invested  nearly  a  million 
pounds  in  the  enterprise,  they  are  at  present  issuing  £750,000  of 
new  debenture  capital  to  provide  funds  to  extend  their  plant  for 
this  purpose.  In  the  last  annual  report  of  the  company  they 
say  :  "  As  regards  plant  indigo,  the  directors  are  prepared  and 
determined  to  meet  this  competition  in  all  its  possible  variations 
in  value.  Much  strange  matter  has  been  published  in  India  as 
to  improvements  in  the  cultivation  and  preparation  of  natural 
indigo,  but  the  illusions  of  the  planters  and  indigo  dealers  are 
destined  to  be  dispelled  before  facts,  which,  although  they  are 
not  known  to  them,  will  make  themselves  more  felt  the  larger 
the  production  of  artificial  indigo  becomes." 

Besides  the  loss  of  material  wealth  which  the  neglect  of  the 
coal-tar  trade  has  involved  to  the  country,  there  is  yet  another 
aspect  of  the  question  which  is  even  of  more  importance  than 
the  commercial  one.  There  can  be  no  question  that  the  growth 
in  Germany  of  a  highly  scientific  industry  of  large  and  far- 
reaching  proportions  has  had  an  enormous  effect  in  encouraging 
and  stimulating  scientific  culture  and  scientific  research  in  all 
branches  of  knowledge.  It  has  reacted  with  beneficial  effect 
upon  the  universities,  and  has  tended  to  promote  scientific 
thought  throughout  the  land.  By  its  demonstration  of  the 
practical  importance  of  purely  theoretical  conceptions  it  has  had 
a  far-reaching  effect  on  the  intellectual  life  of  the  nation.  -How 
much  such  a  scientific  revival  is  wanted  in  our  country  the  social 
and  economic  history  of  the  past  ten  years  abundantly  testifies. 

The  position  with  which  we  are  confronted  is  in  truth  a 
lamentable  one,  and  the  way  out  is  not  so  easy  to  find.  In  1886 
it  could  perhaps  still  be  maintained  that  we  held  the  key  to  the 


200         THE   BRITISH    COAL-TAR   INDUSTRY 

situation  if  we  chose  to  make  use  of  it,  inasmuch  as  the  principal 
raw  products  of  the  colour  manufacture  (tar  oils,  naphthalene, 
anthracene,  soda,  ammonia,  iron,  etc.)  were  in  great  measure 
imported  from  England.  In  a  speech  to  the  Academy  of  Sciences 
of  Munich  in  1878  Professor  von  Baeyer  had  said  :  "Germany, 
which  in  comparison  with  England  and  France  possesses  such 
great  disadvantages  in  reference  to  natural  resources,  has  suc- 
ceeded by  means  of  her  intellectual  activity  in  wresting  from 
both  countries  a  source  of  national  wealth.  Germany  has  no 
longer  to  pay  any  tribute  to  foreign  nations,  but  is  now  receiving 
such  tribute  from  them,  and  the  primary  source  from  which  this 
wealth  originates  has  its  home,  not  in  Germany,  but  in  England. 
It  is  one  of  the  most  singular  phenomena  in  the  domain  of 
industrial  chemistry  that  the  chief  industrial  nation  and  the  most 
practical  people  in  the  world  has  been  beaten  in  the  endeavour 
to  turn  to  profitable  account  the  coal  tar  which  it  possesses.  We 
must  not,  however,  rest  upon  our  oars,  for  we  may  be  sure  that 
England,  which  at  present  looks  on  quietly  while  we  purchase 
her  tar  and  convert  it  into  colours,  selling  them  to  foreign  nations 
at  high  prices,  will  unhesitatingly  cut  off  the  source  of  supply  as 
soon  as  all  technical  difficulties  have  been  surmounted  by  the 
exertions  of  German  manufacturers."1  Professor  von  Baeyer 
could  not  believe  that  the  English  manufacturer  and  capitalist 
would  stand  calmly  by  and  see  an  important  industry  which  had 
had  its  origin  and  early  development  in  his  own  country  taken 
from  beneath  his  nose  without  an  effort  to  retain  it.  Yet  the 
initial  advantages  which  our  natural  resources  afforded  us  have 
been  neglected,  and  now  in  1901  the  conditions  are  completely 
changed.  The  adaptation  of  condensing  plant  to  the  Westphalian 
coke  ovens  has  rendered  Germany,  though  still  a  large  buyer 
from  England,  no  longer  dependent  on  English  tar  and  ammonia  ; 
by  the  development  of  the  ammonia-soda  process  she  no  longer 
requires  English  alkali  ;  whilst  all  other  raw  products  of  the 
colour  industry  can  now  be  purchased  in  the  commercial  centres 
of  Germany  at  least  as  cheaply  as  in  England,  and  some  even  at 
lower  prices.  Through  the  shortsightedness,  ignorance,  and 
want  of  enterprise  of  those  with  whom  the  care  of  the  colour 
industry  in  this  country  has  rested,  the  opportunity  has  been 
allowed  to  pass  for  ever.  The  English  capitalist  has  passed  over 
as  not  sufficiently  profitable  for  his  consideration  an  industry 
1  Quoted  by  Mr  Levinstein,  Jour.  Soc.  Chcm.  Ind.,  1886,  p.  350. 


PROGRESS  DURING  FIFTEEN  YEARS  1886-1900    201 

which  at  present  amounts  to  nine  or  ten  million  sterling  annually, 
and  from  which  his  German  confrere  reaps  a  dividend  of  nearly 
20  per  cent.  The  English  manufacturer  has  considered  that  a 
knowledge  of  the  benzol  market  was  of  greater  importance  than 
a  knowledge  of  the  benzol  theory,  and  after  the  early  but  brilliant 
days  in  the  infancy  of  the  industry,  when  guided  by  such  eminent 
workers  as  Hofmann,  Perkin,  and  Nicholson,  commercial  progress 
and  scientific  investigation  went  hand  in  hand,  but  little  encourage- 
ment has  been  given  here  to  chemical  investigators  and  discoverers. 
The  control  of  the  industry  unfortunately  soon  passed  into  the 
hands  of  men  who  had  no  knowledge  and  absolutely  no  apprecia- 
tion of  the  science  upon  which  their  business  rested,  and,  con- 
cerned only  with  getting  the  ultimate  amount  of  present  profit, 
discouraged  all  scientific  investigations  as  waste  of  time  and 
money.  The  chemist  who  devoted  himself  to  the  elucidation  of 
the  chemical  constitution  of  a  colouring  matter  was  regarded  by 
them  as  an  unpractical  theorist  of  no  value  to  a  manufacturing 
business.  Even  when  he  discovered  new  colouring  matters  of 
commercial  value  they  were  so  blind  to  their  own  interests,  and 
so  incapable  of  believing  that  any  practical  good  could  come  out 
of  such  theoretical  work,  that  in  many  cases  they  refused  to 
patent  or  in  any  way  take  advantage  of  the  discoveries  made  by 
him.  During  recent  years  this  attitude  has  certainly  undergone 
considerable  modification,  and  some  attempt  has  been  made  to 
call  in  the  aid  of  the  science  so  long  neglected.  Certain  firms, 
indeed,  must  be  given  the  credit  of  endeavouring  to  pursue  a 
more  enlightened  policy,  but  these  attempts  have  been  of  a  more 
or  less  sporadic  nature  and  always  directed  too  much  in  the 
expectation  of  realising  immediate  financial  results.  The 
difficulties  which  must  be  encountered  in  the  attempt  to  regain 
the  lost  ground  are  of  necessity  very  great,  and  are  quite  un- 
appreciated by  our  business  men.  It  seems,  in  fact,  to  have  been 
the  opinion  of  the  public  and  the  average  financial  man  that  this 
industry  ought  to  be  easily  won  back  by  us  by  the  establishment 
of  a  few  technical  schools,  the  engagement  of  a  dozen  chemists, 
and  the  investment  of  a  few  thousand  pounds  in  new  plant, 
forgetting  that  the  supremacy  of  our  German  competitors  has 
been  gained  by  years  of  patient  toil,  by  the  work  of  hundreds 
of  trained  chemists,  and  by  the  outlay  of  millions  of  capital. 
Who  can  be  surprised  therefore  if  such  expectations  have  not 
been  realised,  and  if  in  spite  of  some  notable  successes  the  general 


202         THE   BRITISH    COAL-TAR   INDUSTRY 

position  of  the  colour  trade  in  England  at  the  present  day,  at  a 
time  when  even  the  German  trade  is  suffering  from  the  general 
depression,  looks  worse  than  at  any  previous  period  ?  During 
years  of  stagnation  in  this  country  the  German  manufacturers 
have  been  realising  large  profits,  which  they  have  employed  in 
consolidating  their  businesses,  writing  off  the  value  of  their 
buildings  and  plant,  and  accumulating  enormous  reserves  (the 
reserve  of  the  Badische  Company  is  over  a  million  pounds)  : 
they  have  gathered  round  them  perfectly  working  organisations, 
comprising  enormous  staffs  of  scientifically  and  practically  trained 
research  chemists,  factory  chemists  with  highly  specialised  know- 
ledge, chemical  engineers,  dyers,  and  others  ;  their  travellers 
and  agents  are  in  every  part  of  the  globe  ;  by  long  manufacturing 
experience  and  unremitting  endeavour  to  improve  their  processes 
and  plant  they  have  brought  the  yields  and  quality  of  their 
products  to  such  a  state  of  perfection  that  even  when  the  manu- 
facture of  these  products  is  no  longer  covered  by  patents  they 
are  able  to  produce  them  at  a  cost  price  which  is  impossible  to 
anyone  commencing  their  manufacture  ;  they  have  hedged  them- 
selves about  with  a  perfect  stockade  of  many  hundreds  of  patents, 
have  accumulated  in  their  laboratories  thousands  of  intermediate 
products  ready  at  any  time  to  be  subjected  to  any  new  treatment 
or  combination  which  research  or  theory  may  suggest  as  likely 
to  yield  new  results.  By  the  complete  range  of  colours  which 
they  are  able  to  offer  in  each  group  of  dyestuffs,  whether  basic 
colours,  acid  colours  for  wool,  fast  colours  dyeing  on  metallic 
mordants,  diazotisable  colours,  or  direct  colours  for  cotton,  and 
by  the  invaluable  aid  and  assistance  which  they  can  give  the 
dyer  in  his  daily  work  they  are  enabled  to  retain  his  custom 
even  if  it  sometimes  happens  that  a  better  and  a  cheaper  article 
is  offered  him  by  the  home  producer. 

Where,  then,  are  we  to  look  for  an  improvement  ?  Some 
would  find  a  remedy  in  the  imposition  of  heavy  protective  tariffs  ; 
but  such  tariffs  in  France  have  not  availed  to  prevent  a  similar 
state  of  things  there,  and  protection  in  colouring  matters  might 
have  a  very  detrimental  effect  upon  the  textile  industries  of  the 
country.  Others  expect  salvation  from  the  extension  of  technical 
schools  ;  but,  laudable  as  is  the  aim  of  these  institutions,  I  cannot 
see  how  they  can  effect  much  until  their  raw  material  is  of  a  very 
different  character  from  what  it  is  at  present,  and  until  the  public 
can  be  completely  disabused  of  the  fallacy  that  a  year  or  two  of 


PROGRESS  DURING  FIFTEEN  YEARS   1886-1900    203 

technical  training  pumped  into  an  ignorant  schoolboy  will  pro- 
duce a  better  works  chemist  than  a  university  course  of  scientific 
study  laid  upon  the  foundation  of  a  good  general  education. 
Mr  Levinstein  again  bases  his  hopes  for  the  future  upon  a 
reform  of  the  patent  laws,  and  seeks  to  compel  all  patented 
processes  to  be  worked  in  this  country.  Although  I  am  inclined 
to  believe  that  a  portion  of  our  present  troubles  has  been 
brought  about  by  bad  patent  law,  framed  mainly  from  an 
engineering  and  not  from  a  chemical  point  of  view,  which  seems 
specially  designed  to  foster  foreign  trade  at  our  own  expense, 
yet  1  cannot  attribute  to  this  cause  a  too  preponderating  influence, 
and  am  doubtful  whether  its  removal  now  would  materially 
improve  the  position.  The  remedy  for  the  present  state  of 
affairs  must  of  necessity  be  a  slow  one,  and  in  my  opinion  can 
only  be  found  in  a  better  appreciation  of  the  value  of  science 
throughout  the  length  and  breadth  of  the  land.  Until  our 
Government  and  public  men  can  be  brought  to  realise  the 
importance  of  fostering  the  study  of  science  and  of  encouraging 
all  scientific  industries,  until  our  schools  and  universities  ap- 
preciate the  importance  of  a  scientific  education,  until  the  rewards 
for  public  services  in  science  are  made  equal  to  those  in  other 
branches  of  the  public  service,  so  long  will  science  continue  to 
be  held  in  insufficient  esteem  in  our  country,  and  the  best  and 
most  promising  of  our  rising  young  men  will  be  deterred  from 
adopting  chemistry  as  a  profession.  It  is  not  so  much  the 
education  of  our  chemists  which  is  at  fault  as  the  scientific 
education  of  the  public  as  a  whole. 


XII. :    1901 
THE    INDIGO   CRISIS 

(Journal  of  the  Society  of  Dyers  and  Colour  istsy  1901,  p.  157) 

IT  is  now  generally  recognised  that  the  threatened  replace- 
ment of  natural  indigo  by  the  synthetic  product  is  a  matter  not 
only  of  scientific  interest,  but  one  which  may  have  far-reaching 
economic  and  political  consequences  ;  and  mainly  on  this  account 
the  public  interest  has  been  aroused  to  an  extent  which  is  very 
unusual  in  matters  of  this  character.  This  has  been  reflected 
by  questions  in  Parliament  and  correspondence  in  the  Times, 
Nature,  and  other  papers,  as  well  as  in  the  more  directly 
concerned  trade  journals. 

Another  reason  for  the  widespread  interest  evinced  is 
the  very  impressive  manner  in  which  the  problem  of  the 
artificial  production  of  indigotin  has  been  attacked.  The  fact 
that  about  ;£  1,000,000  has  been  spent  by  a  single  German  firm 
in  working  out  the  process  and  in  preparing  for  the  commercial 
introduction  of  the  product  has  appealed  to  the  public 
imagination  as  a  concrete  example  of  German  enterprise,  and 
has  also  led  many  to  realise  the  magnitude  of  the  interests 
involved. 

Within  the  last  few  years  many  papers  and  notes  on  natural 
and  artificial  indigo  have  appeared  in  this  Journal,  and  the 
various  aspects  of  the  subject  will  be  more  or  less  familiar  to 
members,  but  the  general  interest  was  greatly  intensified  by  the 
publication  of  the  lectures  delivered  by  Professor  von  Baeyer  and 
Dr  Brunck  at  the  opening  of  the  Hofmann  House  in  Berlin  in 
October  1900.  Von  Baeyer's  lecture  dealt  chiefly  with  the 
theoretical  aspect  of  the  question,  while  Dr  Brunck  dealt  mainly 
with  the  manufacturing  and  commercial  side. 

Dr  Brunck's  lecture  will  undoubtedly  become  historical,  and 
a  translation  is  given  almost  in  extenso  : — 

204 


THE   INDIGO    CRISIS  205 

THE  HISTORY  OF  THE  DEVELOPMENT  OF  THE 
MANUFACTURE  OF  INDIGO 

In  1868  the  first  complete  synthesis  of  a  vegetable  colouring 
matter  was  accomplished.  Graebe  and  Liebermann  had  pointed 
out  the  path  from  anthracene  to  alizarin,  and  chemical  industry 
hastened  to  follow  that  path.  Magnificent  was  the  result  of 
this  undertaking,  and  the  industry  of  coal-tar  colours  gained  a 
victory  which  justified  its  further  hopes  and  gave  it  the  courage 
to  direct  its  efforts  toward  a  still  higher  goal,  namely,  the 
conquest  of  the  oldest  and  most  important  of  all  colouring 
matters,  indigo. 

The  observation  by  Emmerling  and  Engler,  that  indigo 
could  be  made  from  orthonitroacetophenone,  did  not  supply 
chemical  industry  with  an  effective  base.  However,  after  Ad. 
Baeyer  had  added  the  synthesis  of  isatin  to  his  previous 
synthesis  of  indigo  from  the  former,  he  discovered,  in  1880, 
his  beautiful  synthesis  of  indigo  from  orthonitrophenylpropiolic 
acid,  and  thus,  from  an  industrial  point  of  view,  the  question 
of  manufacturing  indigo  synthetically  assumed  concrete  and 
definite  form. 

Orthonitrophenylpropiolic  acid  is  a  derivative  of  cinnamic 
acid  ;  the  latter  could,  at  that  time,  be  made  by  means  of 
"  Perkin's  reaction "  from  benzaldehyde,  and  this,  since  the 
introduction  of  malachite  green  into  the  arts,  had  become  a 
product  much  employed  in  the  coal-tar  colour  industry,  and  was 
easily  made  from  toluene. 

The  Badische  Anilin-  und  Soda-Fabrik  and  the  Farbwerke 
vorm.  Meister,  Lucius  &  Brilning,  at  Hoechst-on-the-Main, 
acquired  Baeyer 's  patents,  and  now,  in  conjunction  with  the 
inventor,  they  began  the  technical  investigation  of  the  problem, 
which  was  destined  to  occupy  a  period  of  more  than  twenty 
years. 

The  task  was  begun  with  enthusiasm,  and  the  phases  of 
the  individual  syntheses  were  systematically  investigated  and 
studied.  Of  the  circumspection  and  thoroughness  with  which 
the  subject  was  studied  in  all  its  aspects,  but  slight  conception 
is  given  by  the  patents  subsequently  taken  out. 

I  have  before  me  a  tabulation  of  all  the  patents  bearing  on 
this  subject,  and  it  shows  that  in  Germany  alone  there  are 
152  patented  inventions. 


206         THE   BRITISH   COAL-TAR   INDUSTRY 

It  soon  became  possible  to  replace  "  Perkin's  process  "  of 
making  cinnamic  acid  by  the  benzal  chloride  and  sodium  acetate 
process.  Through  this  process,  cinnamic  acid  became  a  cheap 
article  of  manufacture,  instead  of  being  an  expensive  laboratory 
preparation.  But,  on  the  other  hand,  orthonitrocinnamic  acid 
was  at  first,  comparatively,  very  expensive. 

On  nitrating  cinnamic  acid  according  to  the  methods  then 
in  use,  only  a  small  portion  of  the  cinnamic  acid  was  converted 
into  the  orthonitro  compound,  while  the  greater  part  was 
converted  into  the  paranitro  derivative,  which  is  not  available 
for  the  production  of  indigo. 

It  was,  therefore,  necessary  to  alter  this  unfavourable  result, 
and  by  employing  cinnamic  acid  ester  in  place  of  the  free  acid, 
it  was  possible  to  so  conduct  the  operation  that  70  per  cent,  of 
the  acid  could  be  converted  into  the  orthonitro  compound. 

The  subsequent  bromination  of  the  orthonitrocinnamic  acid, 
as  well  as  the  conversion  of  the  resulting  dibromide  of  this 
acid  into  orthonitrophenylpropiolic  acid,  still  offered  many 
difficulties.  But  the  investigations  were  carried  on  with 
enthusiasm  and  with  energy,  and,  as  early  as  the  spring  of  1881, 
they  had  so  far  progressed  that  it  was  possible  to  continously 
manufacture  the  "  propiolic  acid." 

This  process,  however,  was  not  available  for  the  direct 
manufacture  of  indigo,  because  of  the  high  cost  of  production, 
which,  in  spite  of  ease  of  execution  and  of  good  yields,  exceeded 
that  of  the  vegetable  product. 

However,  attempts  were  made  in  other  directions  to  render 
"  propiolic  acid  "  of  use  in  the  arts. 

At  that  time  indigo  printing  was  a  secret  of  but  few  firms, 
and  was  an  operation  requiring  much  experience.  This 
circumstance  suggested  the  conversion  of  "propiolic  acid" 
into  indigo  upon  the  fibre,  and  this  conversion  was  possible  after 
Caro  had  discovered  in  sodium  xanthate  a  reducing  agent 
suitable  for  this  purpose. 

"  Propiolic  acid  "  was  introduced  into  cotton  printing,  and 
was  employed  especially  for  the  production  of  those  delicate 
patterns  which  had  hitherto  been  produced  by  means  of  indigo, 
according  to  the  then  prevailing  methods,  but  only  with  difficulty. 
Unfortunately,  however,  this  success  was  more  of  a  theoretical 
than  of  a  practical  nature,  for  "  propiolic  acid  "  was  never  used 
generally. 


THE    INDIGO    CRISIS  207 

Although  the  results  of  this  painstaking  labour  did  not  fulfil 
the  expectations  of  the  workers,  this  fact  did  not  shake  their 
confidence  nor  diminish  their  activity.  They  recognised  in  the 
results  and  the  experience  so  far  collected,  a  foundation  upon 
which  it  was  possible  to  base  further  work. 

The  year  1882  brought  with  it  Baeyer  and  Drewsen's 
synthesis  of  indigo  from  orthonitrobenzaldehyde  and  acetone. 
This  process,  which  likewise  passed  into  the  possession  of  the 
Farbwerke,  at  Hoechst,  and  of  the  Badische,  was,  in  turn, 
subjected  to  technical  investigation.  The  formation  of  indigo 
was,  indeed,  more  smooth  than  by  means  of  the  cinnamic  acid 
process,  but  the  development  of  a  rational  method  of  manufacture 
of  orthonitrobenzaldehyde  was  beset  with  difficulties  which  at 
first  appeared  insurmountable. 

After  it  had  been  determined  that,  in  spite  of  the  greatest 
possible  variations  of  the  conditions  observed,  the  direct  nitra- 
tion of  benzaldehyde  yielded  only  insufficient  amounts  of  the 
orthonitro  derivative,  which  was  accompanied  by  metanitro- 
benzaldehyde,  which  is  useless  for  indigo  manufacture,  ortho- 
nitrobenzyl  chloride  was  employed  as  the  initial  material  for  the 
production  of  orthonitrobenzaldehyde ;  this  orthonitrobenzyl 
chloride  is  formed  along  with  the  paranitro  body  by  the  nitra- 
tion of  benzyl  chloride,  but  again,  only  in  subordinate  quantities. 
All  attempts  to  arrive  at  a  better  result  failed. 

There  now  remained  the  possibility  of  converting  ortho- 
nitrotoluene  into  orthonitrobenzaldehyde,  either  by  chlorination 
and  subsequent  oxidation,  or  by  direct  oxidation.  These  experi- 
ments were  carried  on  for  years,  but  the  difficulties  in  the  way 
of  completely  chlorinating  orthonitrotoluene,  and  satisfactorily 
working  up  the  chlorination  product  could  not,  for  the  time  being, 
be  overcome. 

When,  in  1886,  the  Badische  Anilin-  und  Soda-Fabrik  had 
found  the  method,  which  has  recently  also  been  patented  by  the 
Societe  des  Usines  du  Rh6ne  ancien.  Gilliard,  Monnet  and 
Cartier,  of  directly  oxidising  methyl  derivatives  of  benzene  to  the 
corresponding  aldehydes,  without  intermediate  conversion  into 
chlorination  products,  hope  was  again  entertained  of  arriving  at 
orthonitrobenzaldehyde  by  oxidising  orthonitrotoluene.  How- 
ever, these  experiments  were  unsatisfactory  and  appeared  to  be 
without  a  practical  future.  The  probability  that  orthonitro- 
benzaldehyde would  serve  as  a  starting-point  for  the  synthetic 


2o8         THE   BRITISH   COAL-TAR   INDUSTRY 

production  of  indigo  became  more  and  more  remote.  The  cost 
of  production  of  synthetic  indigo  was  not  only  dependent  upon 
the  price  of  toluene,  which  was  available  in  but  limited  quantity, 
but  also  upon  the  utilisation  of  the  paranitro  by-product. 

In  1893  the  synthesis  of  indigo  from  orthonitrobenzaldehyde 
was  made  technically  available  by  Kalle  &  Co.,  in  a  manner 
similar  to  the  way  in  which  the  "  propiolic  acid "  process  had 
already  been  applied.  This  firm  succeeded  in  converting  the 
intermediate  product  arising  during  the  formation  of  indigo 
from  the  aldehyde  and  acetone,  namely,  orthonitrophenyllacto 
ketone,  into  a  soluble  bisulphite  compound,  and  this  found 
application  in  printing.  This  product,  which  Kalle  &  Co.  have 
placed  upon  the  market  as  "  indigo  salt,"  is  employed  for  the 
purposes  of  printing  indigo  upon  cotton,  and  is  superior  to 
"  propiolic  acid,"  on  account  of  the  ease  of  its  application. 

It  almost  seemed  as  though  the  investigation  of  this  branch 
of  the  subject  had  ceased.  Several  years  passed  by,  during  which 
not  a  single  new  observation  or  fact  connected  therewith  was 
published.  It  was  not  until  1896,  and  when,  indeed,  it  seemed 
extremely  likely  that  we  should  solve  the  problem  of  a  technical 
indigo  synthesis  along  lines  which  we  had  followed  in  the  mean- 
time, that  it  appeared  from  published  patents  that  this  apparently 
abandoned  field  had,  nevertheless,  been  assiduously  cultivated. 
The  Farbwerke,  at  Hoechst,  had  arrived  at  a  technically  useful 
process  of  converting  orthonitrotoluene  into  orthonitrobenzal- 
dehyde by  treating  the  mixture  of  products  obtained  on 
chlorinating  orthonitrotoluene  with  aniline  or  aniline  sulphonic 
acid,  and  which  can  then  be  readily  isolated.  The  product  so 
obtained  is  converted  into  the  corresponding  benzylidene  com- 
pound, which  latter,  on  treatment  with  acids,  is  converted  into 
orthonitrobenzaldehyde,  and  aniline  or  aniline  sulphonic  acid. 

The  method  of  producing  orthonitrobenzaldehyde  by  direct 
oxidation  of  orthonitrotoluene  to  its  aldehyde  has  since  been 
further  developed  by  the  Soci£t£  des  Usines  du  Rh6ne,  as  well  as 
by  us,  the  Badische  Anilin-  und  Soda-Fabrik,  and  now  yields 
better  results. 

While  it  is  thus  possible  to  produce  orthonitrobenzaldehyde, 
the  conditions  for  the  manufacture  of  indigo  from  this  substance 
are,  at  present,  so  far  favourable,  that,  on  account  of  the  increased 
consumption  of  paranitrotoluene  during  the  last  few  years,  there 
has  arisen  a  corresponding  surplus  of  orthonitrotoluene  as  a  by- 


THE   INDIGO   CRISIS  209 

product.  But  the  amount  of  indigo  which  could  be  manufactured 
therefrom  would  necessarily  be  confined  to  narrow  limits,  and 
could  constitute  but  a  small  part  of  the  consumption. 

If,  however,  this  branch  of  chemical  industry  were  so  situated 
as  to  be  able  to  entirely  disregard  the  utilisation  of  the  paranitro 
by-product,  yet  its  ability  to  expand  and  to  increase  would 
always  be  circumscribed,  and  its  foundation  would  be  uncertain, 
so  long  as  its  initial  material,  toluene,  is  available  in  but  limited 
quantity. 

Permit  me,  in  explanation  of  the  foregoing,  to  call  your 
attention  to  some  statistical  figures.  Benzene  and  toluene  are 
principally  used  in  the  manufacture  of  coal-tar  colours,  and  their 
intermediate  products,  and  their  annual  production  is  at  present 
about  25,000  to  30,000  tons.  On  an  average,  there  will  be  pro- 
duced about  four  parts  of  benzene  for  every  one  part  of  toluene. 
Consequently,  there  are  annually  available  about  5000  or  6000 
tons  of  toluene,  which  are  just  about  sufficient  to  satisfy  the 
present  needs.  The  market  value  of  toluene  is,  as  against 
previous  years,  considerably  higher  than  that  of  benzene,  and 
with  increasing  demand  for  toluene,  its  market  value  must  rise, 
so  long  as  the  amount  of  available  toluene,  which  is  regulated  by 
the  demand  for  benzene,  does  not  increase. 

The  toluene  now  on  the  market  not  being  available  for  the 
manufacture  of  indigo,  it  would  be  necessary  to  obtain  a  new 
supply  of  toluene. 

This  would  mean  that  for  every  ton  of  toluene  thus  obtained, 
four  tons  of  benzene  would  have  to  be  made  ;  some  use  would, 
therefore,  have  to  be  found  for  this  benzene. 

According  to  a  recent  published  statement  concerning  the 
yield  of  indigo  from  toluene,  by  the  newest  and  best  technical 
methods,  one  pound  of  indigo  requires  about  four  pounds  of 
toluene.  Therefore,  the  total  amount  of  toluene  now  produced 
would  suffice,  at  most,  for  the  production  of  one-quarter  of  the 
world's  consumption  of  indigo,  which  may  be  estimated  at  about 
1 1,000,000  pounds  of  100  per  cent,  strength  ;  that  is,  it  would  be 
necessary  to  add  to  the  present  production  of  coal-tar  hydro- 
carbons four  times  the  amount  which  is  made  at  present,  in  order 
to  completely  replace  vegetable  indigo. 

On  account  of  this  state  of  affairs,  we  have  for  a  long  time 
had  but  little  hope  that  the  indigo  syntheses  which  I  have  so  far 
discussed  could  ever  be  capable  of  producing  indigo  in  large 

14 


210         THE   BRITISH   COAL-TAR   INDUSTRY 

quantity,  i.e.  completely  replacing  vegetable  indigo.  It  was, 
therefore,  necessary  for  us  to  direct  our  efforts  towards  obtaining 
an  indigo  synthesis  which  was  based  upon  an  easily  accessible 
initial  material,  and,  above  all,  an  initial  material  whose  supply 
was  sufficient  and  adequate. 

It  was  then — that  is,  in  1890 — that  the  chemical  world  was 
astounded  by  the  discovery  of  Heumann,  namely,  that  indigo 
could  be  obtained  by  melting  phenylglycocoll  with  caustic  potash. 

Through  this  discovery,  the  question  of  the  technical  produc- 
tion of  indigo  was  placed  upon  a  new  basis  ;  the  efforts  of  the 
industry  in  this  direction  were,  by  this  means,  led  into  new 
and  promising  paths.  Promising,  because  this  new  synthesis 
fulfilled  the  first  requirement  of  manufacture  on  a  large  scale, 
namely,  the  cheap  and  easy  production  of  the  required  initial 
materials  which,  in  this  case,  were  solely  aniline,  acetic  acid, 
chlorine,  and  alkali. 

This  invention  was  likewise  acquired  by  the  Badische  Anilin- 
und  Soda-Fabrik,  and  the  Farbwerke  at  Hoechst,  who  at  once 
took  up  the  technical  investigation  of  this  subject,  at  first  with 
the  assistance  of  the  inventor,  but  he,  unfortunately,  died  in 
1894,  and  so  did  not  see  the  completion  of  the  structure  founded 
upon  his  last  researches. 

Although  the  Heumann  synthesis  fulfilled  the  first  require- 
ment for  technical  availability,  namely,  the  easy  supply  of  the 
initial  materials,  nevertheless  it  did  not  satisfy  the  requirements 
with  respect  to  the  yield  of  dyestuff.  Although,  after  numberless 
experiments,  it  was  possible  to  improve  this  yield,  yet  the  im- 
provement was  not  such  as  to  make  manufacture  profitable. 

Experiments  to  obtain  a  more  satisfactory  formation  of  indigo 
by  substituting  for  the  alkali-melt  another  condensation  agent, 
led  us,  and  later  also  the  Farbenfabriken  vorm.  Friedr.  Bayer 
&  Co.,  at  Elberfeld,  to  the  observation  that  an  indigo-sulpho 
acid  could  be  obtained  from  phenylglycocoll  by  the  action  of 
fuming  sulphuric  acid.  However,  this  sulpho  acid  does  not 
possess  the  good  dyeing  properties  which  are  possessed  by  the 
sulpho  acid  obtained  by  the  sulphonation  of  indigo,  and  this 
process  likewise  remained  without  technical  application. 

The  hopes  which  had  been  placed  in  phenylglycocoll  as  the 
basis  for  an  indigo  synthesis  proved  vain. 

Other  glycocolls  behaved  similarly  to  phenylglycocoll.  Tolyl-, 
xylylglycoll,  and  the  glycocolls  of  the  naphthylamines  yielded 


THE   INDIGO   CRISIS  211 

scarcely  any  colouring  matter,  or  such  small  amounts  that  it  was 
impossible  for  them  to  come  into  consideration  at  all.  Further, 
it  had  been  ascertained  that  the  derivatives  of  indigo  were  inferior 
to  indigo  itself,  so  far  as  beauty  of  shade  is  concerned,  and  did 
not  meet  the  demands  of  the  dyer. 

But  Heumann  had  also  found  that  the  glycocoll  of  anthranilic 
acid,  that  is,  phenylglycocoll-orthocarboxylic  acid,  likewise  yields 
indigo  when  treated  in  a  similar  manner.  In  this  case  the  forma- 
tion of  indigo  takes  place  far  more  smoothly,  and  experiments 
soon  made  it  appear  that  this  process  was  capable  of  development 
and  perfection.  But  the  industrial  realisation  of  this  synthesis, 
for  which  the  production  of  anthranilic  acid  as  initial  material 
was  needed,  involved  conditions  far  less  favourable  than  those 
for  the  production  of  phenylglycocoll,  and  was  beset  by  extra- 
ordinary difficulties,  which  at  times  appeared  insurmountable. 
These  could  be  cleared  away  only  by  men  who,  in  addition  to 
possessing  a  thorough  and  a  broad  chemical  knowledge,  likewise 
possessed  great  technical  skill,  and  who  were  experienced  in 
solving  difficult  chemical  problems,  organic  as  well  as  inorganic, 
attacking  them  with  persistence  and  with  ingenuity,  and  finally 
bringing  them  to  a  successful  issue.  Fortunately,  we  had  the 
assistance  of  such  men,  and  after  almost  seven  years  of  labour 
we  succeeded  in  solving  the  problem. 

This  now  brings  me  to  a  discussion  of  the  development  of 
the  process  of  manufacturing  indigo  as  it  is  to-day  carried  on  by 
us.  Phenylglycocoll- or thocarboxylic  acid  is  produced  from 
anthranilic  acid  and  monochloracetic  acid.  For  the  manufacture 
of  the  former  we  were  at  first  dependent  upon  orthonitrotoluene  ; 
orthonitrotoluene  could  be  oxidised  to  nitrobenzoic  acid,  and 
this  could  then  be  reduced,  or  the  operations  could  be  reversed, 
and  the  reduction  product  of  orthonitrotoluene,  namely,  ortho- 
toluidine,  could  be  oxidised  in  appropriate  manner  (e.g.  by  means 
of  its  acetyl  compound)  to  anthranilic  acid.  This  process,  however, 
was  beset  by  the  same  obstacles  as  was  the  manufacture  of  indigo 
from  orthonitrobenzaldehyde.  But  this  was  not  to  prove  fatal, 
for  there  was  a  process  available,  which  had  been  discovered  in 
1890  by  HoogewerfF  and  Van  Dorp,  and  which,  starting  from 
phthalic  acid,  produced  anthranilic  acid.  It  was  A.  W.  von 
Hofmann  who,  by  his  gifted  investigation  of  the  peculiar  action 
of  alkaline  solutions  of  bromine  upon  amines,  furnished  these 
investigators  with  the  basis  for  their  researches.  They  succeeded 


212         THE   BRITISH   COAL-TAR   INDUSTRY 

in  converting  phthalimide  into  anthranilic  acid  by  means  of  an 
alkaline  solution  of  bromine. 

With  phthalic  acid  as  initial  material  for  anthranilic  acid, 
naphthalene  became  the  initial  material  of  the  indigo  synthesis, 
and  this  fact  created  the  first  reliable  basis  for  indigo  manufacture 
on  a  large  scale. 

From  this  time  on  I  was  firmly  convinced  that  the  path  which 
was  now  being  followed  must  lead  to  the  achievement  of  the 
great  object  :  The  replacement  of  vegetable  indigo  by  synthetic 
indigo. 

In  fact,  naphthalene  is  an  initial  material  which,  for  the  pur- 
pose of  indigo  manufacture,  is  available  in  unlimited  quantities. 
Based  upon  reliable  information,  I  estimate  that  the  amount  of 
coal  tar  which  is  annually  treated  for  its  contained  hydrocarbons, 
and  which  I  assume  to  be  two-thirds  of  the  total  world's  output, 
contains  from  40,000  to  50,000  tons  of  naphthalene,  and  of  this 
only  about  15,000  tons,  which  correspond  to  the  present-day 
consumption,  are  isolated.  For  the  purposes  of  indigo  manu- 
facture, therefore,  there  remain  at  least  25,000  tons  of  naphthalene 
which  hitherto,  on  account  of  lack  of  market,  were  burned  to 
lamp-black  or  remained  dissolved  in  the  heavy  oils,  but  which 
can  also  be  isolated  by  the  same  means  and  at  the  same  cost  as 
the  aforementioned  15,000  tons. 

The  naphthalene  in  this  way  available  is,  however,  more  than 
sufficient  to  cover  the  amount  required  for  the  manufacture  of 
the  world's  consumption  of  indigo. 

The  auspices  for  the  solution  of  this  great  problem  were 
therefore  favourable,  and  it  became  necessary  to  bring  to  bear 
upon  its  accomplishment  all  the  ability  and  energy  and  all  the 
expedients  and  means  known  to  the  present-day  industry,  and  to 
make  use  of  all  the  experience  which  had  been  acquired  in  manu- 
facturing operations  in  the  course  of  a  great  number  of  years, 
and  to  spare  no  labour  and  no  expense  in  order  to  make  every- 
thing, which  could  possibly  contribute  to  its  success,  serviceable 
to  this  undertaking. 

And,  in  fact,  there  was  a  great  work  still  to  be  performed. 
The  systematic  investigation  of  the  individual  phases  of  the 
process  occupied  the  attention  and  activity  of  our  best  men 
through  many  years. 

We  did,  indeed,  at  that  time  possess  the  best  process  then 
known  for  the  manufacture  of  phthalic  acid.  This  consisted  in 


THE   INDIGO   CRISIS  213 

the  oxidation  of  naphthalene  by  means  of  chromic  acid,  and  it  had 
been  first  developed  and  perfected  by  us,  and  had  been  in  opera- 
tion for  twenty  years.  But,  since  phthalic  acid  so  produced  was 
still  too  expensive,  and  it  was  not  to  be  expected  that  this  method 
of  manufacture  which  had  been  employed  by  us  for  so  long  a 
time  was  still  susceptible  of  an  essential  improvement,  it  was 
necessary  to  bring  about  the  oxidation  of  naphthalene  by  a 
cheaper  means. 

Our  chemist,  E.  Sapper,  succeeded  in  finding  an  entirely  new 
method  for  the  production  of  phthalic  acid,  which  consisted  in 
heating  naphthalene  with  highly  concentrated  sulphuric  acid. 

A  most  comprehensive  series  of  experiments  was  carried  out 
to  develop  this  process  to  practical  utility.  The  effect  of  addi- 
tions of  the  most  various  kinds  to  the  reaction  mass  was  tried, 
and,  in  the  end,  mercury  was  found  to  be  an  agent  which  brought 
the  yields  to  a  satisfactory  point.  Even  though  an  accident, 
namely,  the  destruction  of  a  pocket  containing  mercury,  was  an 
assistance,  this  accident  merely  hastened  the  solution  of  the 
problem.  But  without  it  the  object  would  certainly  have  been 
achieved. 

On  a  small  scale,  the  results  were  perfect.  But  the  manu- 
facture on  a  large  scale  required  enormous  efforts,  much  time  and 
patience,  and  the  question  of  apparatus  especially  required  many 
and  very  expensive  experiments  for  its  solution. 

In  the  first  place,  the  oxidation  of  the  naphthalene  required 
large  amounts  of  strong  sulphuric  acid,  and  the  nearly  complete 
and  most  advantageous  recovery  of  this  was  the  prime  condition 
of  success.  Had  we  been  compelled  to  accomplish  this  regenera- 
tion of  the  sulphuric  acid  in  lead  chambers,  then  this  new  process 
would  hardly  have  offered  any  advantages  over  the  chromic-acid 
process. 

It  was  at  this  stage  that  our  new  sulphuric-acid  process,  which 
was  developed  by  R.  Knietsch,  stood  us  in  good  stead.  The 
contact  process,  which  had  become  available  for  the  industrial 
production  of  fuming  sulphuric  acid,  through  the  suggestion  of 
C.  Winkler,  in  1875,  has  since  been  developed  by  us  so  that 
the  production  of  sulphuric  anhydride,  by  the  direct  union  of 
pyrites  burner  gases — that  is,  of  sulphur  dioxide  and  the  oxygen 
of  the  air, — has  now  become  more  profitable  for  the  manufacture 
of  sulphuric  acid  than  is  the  lead-chamber  process.  This  has 
been  published  both  in  chemical  literature  and  in  our  patents. 


2i4         THE   BRITISH   COAL-TAR   INDUSTRY 

Our  new  process  of  making  phthalic  acid  was,  therefore, 
directly  dependent  upon  this  sulphuric  acid  manufacture,  since 
the  latter  made  it  possible  to  directly  convert  the  sulphur  dioxide 
arising  from  the  oxidation  of  the  naphthalene  into  concentrated 
sulphuric  acid  in  the  cheapest  possible  manner. 

You  may  be  able  to  form  an  idea  as  to  the  part  which  this 
sulphuric-acid  manufacture  plays  in  our  process  from  the  fact 
that,  from  our  present  production  of  phthalic  acid,  there  result 
annually  35,000  to  40,000  tons  sulphur  dioxide  which  we  must 
reconvert  into  sulphuric  anhydride.  For  this  purpose  a  plant  of 
about  the  same  size  is  required  as  for  an  equal  weight  of  iron 
pyrites. 

Now,  and  only  now,  was  the  cycle  of  the  process  completed. 
The  oxygen  of  the  air  now  converts  naphthalene  into  phthalic 
acid  in  the  cheapest  manner  possible,  and  our  new  sulphuric-acid 
process  thus  becomes  one  of  the  foundations  of  indigo  manu- 
facture. This  is  a  firm  foundation  ! 

While  these  labours,  which  extended  from  1891  until  1897, 
were  in  progress,  the  manufacture  of  the  other  initial  materials 
was  investigated  and  worked  out  with  the  same  energy. 

Large  amounts  of  chlorine  are  required  in  the  manufacture 
of  the  requisite  amount  of  chloracetic  acid,  and  also  for  the 
oxidation  of  phthalimide  to  anthranilic  acid,  and  it  was  therefore 
necessary  to  create  a  cheap  source  of  chlorine.  Even  now  we 
must  chlorinate  4,400,000  Ib.  of  glacial  acetic  acid — an  amount 
of  acetic  acid  equivalent  to  130,000  cubic  yards  of  wood  ! 
Neither  Weldon's  process  nor  Deacon's  process  would  answer 
our  purpose  ;  the  former,  because  the  chlorine  it  yielded  was  too 
expensive,  and  the  latter,  because  its  chlorine  was  too  dilute. 

In  the  meantime,  however,  the  researches  on  the  electrolytic 
production  of  chlorine  from  alkali  chlorides  had  made  consider- 
able strides.  A  number  of  electrolytic  processes  were,  indeed, 
known  by  name,  but  their  real  value  was  not  known,  and  it  was 
therefore  necessary  to  select  from  these  that  process  which  was 
best  adapted  to  the  requirements  of  indigo  manufacture  ;  and, 
since  great  expenditure  is  involved  in  plant  of  this  nature,  it  was 
necessary  to  exercise  the  greatest  caution  in  this  selection. 

We  believe  that  we  are  justified  in  holding  that,  through 
acquiring  the  process  of  the  Chemische  Fabrik  Elektron  in 
Griesheim-on-the-Main,  we  possess  the  best  process  of  the 
present  day. 


THE   INDIGO   CRISIS  215 

Only  in  point  of  purity  the  resulting  chlorine  did  not  satisfy 
our  high  requirements,  and  here  our  process  for  the  liquefaction 
of  chlorine  enabled  us  to  convert  it  into  its  purest  form.  The 
development  of  the  process  for  the  production  of  chloracetic  acid 
was  also  a  difficult  task  ;  however,  this  branch  of  manufacture, 
which,  at  first,  was  most  disagreeable,  has  finally  developed  into 
a  comparatively  simple  manufacturing  operation. 

The  manufacture  of  phthalimide,  of  anthranilic  acid,  and  of 
phenylglycocoll-orthocarboxylic  acid  itself,  the  real  mother-sub- 
stance of  indigo,  was  more  difficult  than  it  at  first  appeared  to  be. 
Whole  series  of  systematic  experiments  had  to  be  carried  out,  in 
order  to  determine  the  conditions  under  which  it  was  possible  to 
obtain  a  maximum  yield  of  pure  acid. 

One  of  the  most  difficult  problems  was  the  proper  carrying 
out  of  the  melting  process  on  the  large  scale  ;  that  is,  the  con- 
version of  phenylglycocoll-orthocarboxylic  acid,  by  heating  it 
with  alkali,  into  the  leuco  compound  which,  on  oxidation  with 
air,  yields  indigo.  These  experiments,  in  the  execution  of  which 
R.  Knietsch,  the  able  and  successful  manager  of  our  indigo  de- 
partment, and  P.  Seidel  took  most  active  part,  were  carried  on 
for  years.  New  apparatus  had  to  be  invented  and  constructed 
before  the  process  was  so  far  developed  as  to  be  adapted  for 
continuous  manufacture. 

It  may  be  mentioned,  in  passing,  that  during  the  determina- 
tion of  those  conditions  which  would  bring  about  a  satisfactory 
course  of  the  melting  operation,  free  indoxylic  acid  was  manu- 
factured which,  under  the  name  "  indophor,"  has  found  applica- 
tion in  cotton  printing,  namely,  for  the  production  of  indigo 
upon  the  fibre  in  a  manner  similar  to  that  in  which  "  propiolic 
acid  "  and  "  indigo  salt "  are  employed. 

The  indigo  which  is  obtained  from  the  water  solution  of  this 
melt,  by  means  of  air,  is  crystalline.  In  those  cases  where  an 
especially  fine  state  of  division  is  desired,  such  as  in  the  fermenta- 
tion vat,  the  so-obtained  indigo  is  converted  into  a  sulphate  by 
means  of  sulphuric  acid,  and  this  is  decomposed  with  water,  and 
is  thus  reconverted  into  the  original  indigo  in  the  form  of  a  loose 
powder,  which  is  extremely  easily  soluble  in  the  vat. 

I  have  attempted  to  present  to  you,  in  a  short  sketch,  the 
history  of  the  development  of  a  new  manufacture,  and  it  now 
devolves  upon  me  to  more  clearly  bring  out  a  few  considerations 
which  may  be  adapted  to  indicate,  at  least,  the  influence  of  this 


216         THE   BRITISH   COAL-TAR   INDUSTRY 

manufacture  upon  the  development  of  important  industries,  as 
well  as  upon  future  economic  changes. 

The  advantages  which  the  synthetic  product  possesses  over 
the  vegetable  product  have  been  presented  so  frequently  on  other 
occasions,  that  in  this  direction  I  can  be  very  brief. 

The  uniformity  and  the  constant  strength  of  synthetic  indigo, 
its  absolute  freedom  from  foreign  admixture,  its  easy  reducibility 
when  finely  divided,  and  the  ease  of  application  which  is  thereby 
secured  for  the  dyer,  are  to  be  mentioned  as  its  principal  ad- 
vantages, as  against  the  constantly  varying  strength  and  the 
difficult  reducibility  of  the  commercial  brands  of  vegetable  indigo. 
These  advantages  free  the  dyer  from  oppressive  dependence  upon 
the  dealers,  because,  on  account  of  lack  of  methods  of  accurate 
determination,  he  has  been  obliged  to  purchase  his  stock,  not 
according  to  its  actual  value,  but  according  to  external  and 
easily  misleading  characteristics.  These  advantages  of  the 
synthetic  product  now  guarantee  him  absolute  uniformity  and 
perfect  quality. 

In  spite  of  these  advantages,  synthetic  indigo  had  to  over- 
come many  obstacles  which  were  placed  in  the  way  of  its  intro- 
duction. It  was  but  natural  that  its  quality  was  discredited  by 
those  to  whose  interest  it  was  to  do  so  ;  this  was  done,  for 
example,  by  stating  that  the  impurities  contained  in  vegetable 
indigo,  and  which  were  absent  from  the  synthetic  product,  were 
essential  to  the  dyeing  process.  Again,  it  was  claimed  that  the 
indigo  which  we  brought  into  commerce  was  nothing  more  nor 
less  than  refined  vegetable  indigo  ! 

One  of  the  greatest  obstacles  in  the  way  of  its  introduction, 
however,  was  the  fact  that  the  conception  of  a  "chemical 
individual "  is  for  the  most  part  unknown  to  those  who  are  not 
chemists.  It  was  impossible  for  such  to  comprehend  the  fact 
that  two  bodies  of  different  origin,  such  as  vegetable  indigo  and 
synthetic  indigo,  could  be  identical ;  synthetic  indigo  was 
designated  as  a  substitute  and  adulterant  of  vegetable  indigo, 
and  it  was  attempted  to  place  it  on  the  same  plane  with  those 
aniline  dyestuffs  that  dye  a  similar  shade. 

But  such  deceptions  and  carpings  could  not  long  prevail 
against  the  facts. 

Synthetic  indigo,  in  accordance  with  its  very  great  purity, 
yields  brighter  shades.  Curiously  enough,  this  circumstance  also 
acted  at  first,  though  of  course  only  in  isolated  instances,  as  an 


THE   INDIGO   CRISIS  217 

obstacle  to  its  introduction  ;  thus,  for  example,  one  or  two  of  the 
German  military  authorities  raised  an  objection  because  cloth 
dyed  with  our  pure  indigo  possessed  a  somewhat  brighter  shade 
than  did  cloth  which  had  been  dyed  according  to  the  old  method, 
with  impure  indigo,  and  which  served  as  the  standard  of 
comparison. 

On  account  of  its  easy  reducibility  and  uniformity,  dyeing 
with  pure  indigo  has  become  an  operation  equal  in  ease  and 
simplicity  with  the  dyeing  with  any  other  ordinary  dyestuff, 
whilst,  formerly,  it  was  only  possible  after  acquiring  considerable 
experience  by  prolonged  practice  to  obtain  a  desired  shade 
with  certainty,  when  using  vegetable  indigo,  which,  as  is  known, 
is  available  only  in  brands  of  the  most  varying  degrees  of 
purity.  This  latter  art,  which  is  often  inherited  from  genera- 
tion to  generation,  has  lost  much  of  its  value  through  synthetic 
indigo,  and  on  this  account  the  new  product  was  accorded  a 
most  unfriendly  reception  by  many  an  indigo  dyer  who  was 
conscious  of  his  own  especial  skill. 

When,  in  July  1897,  we  had  succeeded  in  so  far  reducing 
the  cost  of  manufacture  of  synthetic  indigo  that  we  could  suc- 
cessfully compete  with  the  lowest  price  which  vegetable  indigo 
had  ever  reached,  we  decided  to  first  erect  a  plant  which  would 
enable  us  to  supply  the  consumption  of  this  colouring  matter 
in  Germany,  and  in  so  doing  arrangements  were  made  so  that, 
in  case  of  success,  our  capacity  could  be  increased  at  will. 

As  we  were  ignorant  as  to  how  cheaply  the  planters  could 
supply  vegetable  indigo  in  the  course  of  the  impending  conflict, 
and  also  because  there  is  a  possibility  that  a  cheaper  and  simpler 
process  for  the  manufacture  of  indigo  might  be  found,  our 
venture  was  subject  to  a  very  great  risk  ;  because,  for  its  suc- 
cessful prosecution,  extraordinary  financial  resources  were 
necessary,  and,  as  a  matter  of  fact,  we  have,  to-day,  invested 
about  £900,000  for  this  purpose. 

Up  to  the  present,  the  results  which  we  have  achieved 
correspond  to  our  expectations,  and  we  hope  to  be  victorious  in 
the  long  and  arduous  struggle  that  is  before  us. 

Formerly,  the  value  of  the  indigo  annually  produced  was 
estimated  at  £4,000,000  to  £5,000,000  ;  even  at  the  present 
prices,  which  are  essentially  lower,  the  value  may  still  be 
£2,500,000  to  £3,000,000. 

Although,  up  to  the  present,  we  have  succeeded  in  securing 


218         THE   BRITISH   COAL-TAR   INDUSTRY 

to  German  industry  but  a  part  of  this  sum,  and  thereby  making 
the  German  consumer  independent  of  foreign  countries,  and  in 
retaining  for  Germany  those  sums  of  money  which  have  hitherto 
been  paid  to  foreigners  for  indigo,  yet  it  is  probably  merely  a 
question  of  time  when  the  entire  consumption  of  indigo  will 
be  provided  for  synthetically,  and  thus  large  sums  will  pass  from 
foreign  countries  to  Germany. 

The  quantity  of  indigo  which  we  produce  annually,  even  at 
this  date,  would  require  the  cultivation  of  an  area  of  more  than 
a  quarter  of  a  million  acres  of  land  (390  square  miles)  in  the 
home  of  the  indigo  plant.  The  first  impression  which  this  fact 
may  be  likely  to  produce  is  that  the  manufacture  of  indigo 
will  cause  a  terrible  calamity  to  arise  in  that  country  ;  but 
perhaps  not.  If  one  recalls  to  mind  that  India  is  periodically 
afflicted  with  famine,  one  ought  not,  without  further  considera- 
tion, to  cast  aside  the  hope  that  it  might  be  good  fortune  for 
that  country  if  the  immense  areas,  now  devoted  to  a  crop  which 
is  subject  to  many  vicissitudes  and  to  violent  market  changes, 
were  at  last  to  be  given  over  to  the  raising  of  breadstuff's  and 
other  food-products.  For  myself,  I  do  not  assume  to  be  an 
impartial  adviser  in  this  matter,  but,  nevertheless,  I  venture  to 
express  my  conviction  that  the  Government  of  India  will  be 
rendering  a  very  great  service  if  it  should  support  and  aid  the 
progress,  which  will  in  any  case  be  irresistible,  of  this  impending 
change  in  the  cultivation  of  that  country,  and  would  support 
and  direct  its  methodical  and  rational  execution. 

I  have  reached  the  end  of  my  lecture.  You  have  seen  that 
this  new  industry  is  not  an  unexpected  gift  fallen  from  the 
heavens,  but  that  in  order  to  complete  the  task  the  intellectual 
labour  and  the  industry  of  many  men  had  to  be  co-ordinated, 
in  an  organised  attempt  to  attain  a  definite  object,  for  a  number 
of  years,  and  throughout  a  considerable  period  when  success 
could  by  no  means  be  regarded  as  certain.  The  pre-requisites 
for  practical  indigo  synthesis  were  supplied  by  the  results  of 
long  years  of  scientific  labour.  All  the  expedients  of  an  ad- 
vanced art  were  at  command,  and  it  is  to  the  wide  knowledge,  to 
the  industry,  to  the  energy,  and  to  the  faithfulness  to  duty  which 
characterise  our  German  chemists  that  the  final  completion  of 
the  work  is  due,  a  work  of  which  we  wish  that  it  may  signify  an 
advance  in  civilisation,  and  which  we  hope  will  be  an  honour  to 
the  German  chemical  industry  and  a  blessing  to  our  country. 


THE   INDIGO   CRISIS  219 


OTHER  OPINIONS 

In  a  recent  lecture  before  the  Society  of  Arts,1  Professor 
Meldola  discussed  the  various  synthetical  processes  for  the 
manufacture  of  indigo,  and  more  especially  the  manufacture  of 
"  indigo  pure  "  by  the  Badische  Aniline  Co. 

With  regard  to  the  all-important  point  of  cost  of  production, 
Professor  Meldola  offers  the  following  remarks  :  —  "  Naphthalene 
is  the  hydrocarbon  which  exists  in  coal  tar  to  a  larger  extent  than 
any  other.  The  average  quantity  is  about  8  per  cent.,  and  there 
is  any  amount  of  it  to  be  had.  The  whole  of  the  naphthalene  in 
tar  is  not  at  present  extracted,  the  chief  supply  being  furnished 
by  the  middle  or  carbolic  acid  fraction.  Mr  T.  Wilton,  of  the 
Gaslight  and  Coke  Co.,  states  that  that  company  produces  about 
19^-  million  gallons  of  tar  annually.  This  company  alone  would 
thus  be  able  to  supply  over  15  million  pounds  of  naphthalene 
per  annum.  The  purified  hydrocarbon  has  a  present  market 
value  of  £18,  los.  per  ton,  which  is  less  than  one  penny  per 
pound.  From  an  estimate  supplied  by  Mr  Charles  Tyrer,  of 
Thomas  Tyrer  &  Co.,  it  appears  that  technical  chloracetic  acid 
might  probably  be  made  at  about  is.  id.  per  pound.  As  regards 
the  supply  of  naphthalene,  it  has  been  suggested  that  the  pro- 
duction from  coal  tar  would  be  insufficient  to  meet  the  demand, 
supposing  that  all  the  indigo  now  required  were  made  syntheti- 
cally." Figures  given  by  Dr  Brunck  refute  this  statement. 
(See  page  212.) 

It  may  be  added  also  that  coal  tar  is  not  the  only  source  of 
naphthalene,  since  a  considerable  quantity  of  this  hydrocarbon 
is  contained  in  coke-oven  tar.  Moreover,  petroleum  may  be 
looked  upon  as  a  potential  source  of  naphthalene,  since  the 
crude  naphtha,  consisting  chiefly  of  heptane  and  octane,  on 
decomposition  by  heat,  gives  a  mixture  of  hydrocarbons  con- 
taining, according  to  Worstall  and  Burwell,2  12*5  parts  benzene, 
3  parts  toluene,  3  parts  xylene,  and  3*6  parts  naphthalene  for 
100  parts  naphtha. 

With  respect  to  the  probabilities  of  the  issue  of  the  conflict 
between  natural  and  synthetic  indigo,  Professor  Meldola,  while 
not  regarding  the  cause  of  the  indigo  planters  as  a  forlorn  one, 


1  Jour.  Soc.  Arts,  iQth  April  1901. 

2  Amer.  C  hem.  Jour.,  1897,  x.  815. 


220         THE   BRITISH    COAL-TAR   INDUSTRY 

considers  the  outlook  as  gloomy,  in  view  of  the  probability  of 
the  Badische  process  being  still  further  perfected  and  cheapened.1 

The  magnitude  of  the  operations  of  the  large  German  colour 
works  has  often  been  the  subject  of  remark  in  these  columns, 
but  their  remarkable  growth  and  the  unbounded  enterprise  with 
which  they  are  conducted  is  very  succinctly  put  in  the  following 
paragraph  from  Professor  Meldola's  lecture  : — 

"  The  factory  at  Ludwigshafen  employs  148  scientific  chemists, 
75  engineers  and  technical  experts,  and  303  members  of  the 
mercantile  staff.  In  1865  they  commenced  with  30  workmen, 
and  they  now  employ  6000.  The  consumption  of  coal  is  about 
243,000  tons  per  annum.  Water  is  supplied  to  the  factory  to 
the  extent  of  20,000,000  cubic  metres  (4,400,000,000  gallons) 
annually  ;  they  make  12,000,000  kilograms  (11,400  tons)  of  ice, 
and  12,000,000  cubic  metres  (420,000,000  cubic  feet)  of  coal 
gas  in  the  course  of  a  year.  102  boilers  supply  steam,  which 
serves  for  heating  purposes  and  for  driving  253  steam  engines. 
The  factory  comprises  an  area  of  206  hectares  (510  acres),  of 
which  317,429  square  metres  (378,000  square  yards)  are  built 
upon." 

In  October  of  last  year  a  Commission  was  appointed  by  the 
Government  of  India  to  inquire  into  the  condition  of  the  sugar 
and  indigo  industries,  and  their  report,  which  has  already  been 
issued,  is  reviewed  in  the  Times  of  I5th  April  1901.  It  is  there 
stated  that  the  average  acreage  in  India  under  indigo  during  the 
five  years  1893-98  was  1,406,000  acres,  but  in  1899  it  was  only 
1,027,000  acres,  and  in  1900,  964,000  acres.  In  1895-96  the 
exports  amounted  to  187,000  cwts.,  but  steadily  declined  to 
1 1 1,000  cwts.  in  1899-1900.  This  was  partly  due  to  unfavour- 
able seasons  ;  but  in  the  past  experience  of  the  trade,  a  low  output 
was  always  accompanied  by  an  enhanced  price  ;  whereas,  in  the 
period  referred  to,  the  price  in  the  poor  years  did  not  show  the 
same  recovery,  and  the  Commissioners  conclude  that  it  is  reason- 
able to  anticipate  that  the  competition  of  synthetic  indigo  will 
prevent  any  future  increase  in  the  price  of  vegetable  indigo, 
and  that  any  further  reduction  in  price  would  be  ruinous  to  the 
planters  in  a  bad  season. 

On  the  other  hand,  the  planters,  who  take  a  more  sanguine 
view  than  the  Commissioners,  consider  that  by  improved  culti- 

1  An   interesting   discussion    of   this  point  will  be  found  in  a  paper  by 
Dr  Levinstein  (see  Jour.  Soc.  Dyers  and  Colourists,  1901,  p.   138). 


THE   INDIGO   CRISIS  221 

vation  and  mode  of  extraction  and  manufacture,  a  greatly  increased 
yield  will  enable  them  to  place  a  much  improved  article  on  the 
market  at  a  cheaper  rate.  This  side  of  the  question  is  well 
argued  in  Mr  Rawson's  paper,  read  before  a  meeting  of  planters 
and  merchants  in  Calcutta,  and  abstracted  in  the  Journal  of  the 
Society  of  Dyers  and  Co  tourists  (1901,  p.  103). 

Under  the  title  of  "  The  Downfall  of  Natural  Indigo,"  Pro- 
fessor Armstrong, on  1 5th  April,  published  a  long  letter  in  the  Times 
discussing  Dr  Brunck's  lecture.  He  takes  it  pretty  much  for 
granted  that  the  indigo  industry  is  doomed  to  rapid  extinction, 
and  makes  this  a  text  for  a  vigorous  attack  on  the  supineness  of 
English  business  men  in  regard  to  the  adoption  of  scientific 
methods  and  scientific  assistance. 

In  a  letter  to  Nature  on  "  Indigo  and  Sugar,"  Dr  F.  Molwo 
Perkin  also  pertinently  asks,  in  reference  to  the  above-quoted 
figures  of  the  staff  at  the  Badische  works,  if  there  "are  148 
scientific  chemists  employed  by  manufacturers  in  the  whole  of 
the  United  Kingdom  ?  " 

The  present  crisis  in  the  indigo  industry  may  possibly  benefit 
others  indirectly  by  inducing  them  to  take  advantage,  more  fully 
than  has  been  the  case  in  the  past,  of  scientific,  and  therefore 
rational  and  economical,  methods  of  manufacture. 


XIII. :    1902 

APPLIED    CHEMISTRY,    ENGLISH 
AND    FOREIGN 

BY  SIR  J.  DEWAR,  M.A.,  LL.D.,  D.Sc.,  F.R.S. 
(Abstract  from  Presidential  Address,  British  Association,  Belfast,  1902) 

THE  diplomatic  and  consular  reports  published  from  time  to 
time  by  the  Foreign  Office  are  usually  too  belated  to  be  of  much 
use  to  business  men,  but  they  sometimes  contain  information 
concerning  what  is  done  in  foreign  countries  which  affords  food 
for  reflection.  One  of  these  reports,  issued  a  year  ago,  gives  a 
very  good  account  of  the  German  arrangements  and  provisions 
for  scientific  training,  and  of  the  enormous  commercial  demand 
for  the  services  of  men  who  have  passed  successfully  through  the 
universities  and  Technical  High  Schools,  as  well  as  of  the  wealth 
that  has  accrued  to  Germany  through  the  systematic  application 
of  scientific  proficiency  to  the  ordinary  business  of  life. 

Taking  these  points  in  their  order,  I  have  thought  it  a  matter 
of  great  interest  to  obtain  a  comparative  view  of  chemical  equip- 
ment in  this  country  and  in  Germany,  and  I  am  indebted  to 
Professor  Henderson  of  Glasgow,  who  last  year  became  the 
secretary  of  a  committee  of  this  Association  of  which  Professor 
Armstrong  is  chairman,  for  statistics  referring  to  this  country, 
which  enable  a  comparison  to  be  broadly  made.  The  author  of 
the  consular  report  estimates  that  in  1901  there  were  4500 
trained  chemists  employed  in  German  works,  the  number  having 
risen  to  this  point  from  1700  employed  twenty-five  years  earlier. 
It  is  difficult  to  give  perfectly  accurate  figures  for  this  country, 
but  a  liberal  estimate  places  the  number  of  works  chemists  at 
1500,  while  at  the  very  outside  it  cannot  be  put  higher  than 
somewhere  between  1500  and  2000.  In  other  words,  we  cannot 


222 


APPLIED  CHEMISTRY,  ENGLISH  AND  FOREIGN  223 

show   in    the    United   Kingdom,   notwithstanding  the    immense 
range  of  the  chemical  industries  in  which  we  once  stood  promi- 
nent, more  than  one-third  of  the  professional  staff  employed  in 
Germany.     It  may  perhaps  be  thought  or  hoped  that  we  make 
up  in  quality  for  our  defect  in  quantity,  but  unfortunately  this  is 
not  the  case.     On  the  contrary,  the  German  chemists  are,  on  the 
average,  as  superior    in    technical  training  and  acquirements  as 
they  are    numerically.     Details   are  given   in  the  report  of  the 
training  of  633  chemists  employed  in  German  works.     Of  these, 
69  per  cent,  hold  the  degree  of  Ph.D.,  about   10  per  cent,  hold 
the  diploma  of  a  Technical  High  School,  and  about  5  per  cent, 
hold  both    qualifications.     That  is   to   say,  84    per   cent,    have 
received  a  thoroughly  systematic  and  complete  chemical  training, 
and  74  per  cent,  of  these  add   the  advantages  of   a  university 
career.     Compare   with    this  the  information  furnished  by  500 
chemists  in    British    works.     Of   these  only   21    per    cent,    are 
graduates,  whilst  about  10  per  cent,  hold  the  diploma  of  a  college. 
Putting   the    case   as  high  as  we  can,   and   ignoring   the    more 
practical  and  thorough  training  of  the  German  universities,  which 
give  their  degrees  for  work  done,  and  not  for  questions  asked 
and  answered  on  paper,  we  have  only  3 1  per  cent,  of  systematic- 
ally trained  chemists  against  84  per  cent,  in  German  works.     It 
ought  to  be  mentioned  that  about  2 1   per  cent,  of  the  500  are 
Fellows  or  Associates  of   the  Institute  of  Chemistry,  whatever 
that  may  amount  to  in  practice,  but  of  these  a  very  large  number 
have  already  been  accounted  for  under  the  heads  of  graduates 
and  holders  of   diplomas.     These    figures,  which  I  suspect  are 
much  too  favourable  on  the  British  side,  unmistakably  point  to 
the  prevalence  among  employers  in  this  country  of  the  antiquated 
adherence  to  rule  of  thumb,  which  is  at  the  root  of  much  of  the 
backwardness  we  have  to  deplore.     It  hardly  needs  to  be  pointed 
out  to  such  an  audience  as  the  present  that  chemists  who  are 
neither  graduates  of  a  university,  nor  holders  of  a  diploma  from 
a   technical   college,   may   be   competent   to    carry   on   existing 
processes  according  to  traditional  methods,  but  are  very  unlikely 
to  effect  substantial  improvements,  or  to  invent  new  and  more 
efficient  processes.     I  am  very  far  from  denying  that  here  and 
there  an   individual   may   be   found   whose   exceptional   ability 
enables  him  to  triumph  over  all  defects  of  training.     But  in  all 
educational  matters  it  is    the   average   man  whom  we   have  to 
consider,  and   the  average  ability  which   we   have   to   develop. 


224         THE   BRITISH   COAL-TAR    INDUSTRY 

Now,  to  take  the  second  point — the  actual  money  value  of  the 
industries  carried  on  in  Germany  by  an  army  of  workers  both 
quantitatively  and  qualitatively  so  superior  to  our  own.  The 
consular  report  estimates  the  whole  value  of  German  chemical 
industries  at  not  less  than  fifty  millions  sterling  per  annum. 
These  industries  have  sprung  up  within  the  last  seventy  years,  and 
have  received  enormous  expansion  during  the  last  thirty.  They 
are,  moreover,  very  largely  founded  upon  basic  discoveries  made 
by  English  chemists,  but  never  properly  appreciated  or  scientific- 
ally developed  in  the  land  of  their  birth.  I  will  place  before  you 
some  figures  showing  the  growth  of  a  single  firm  engaged  in  a 
single  one  of  these  industries — the  utilisation  of  coal  tar  for  the 
production  of  drugs,  perfumes,  and  colouring  matters  of  every 
conceivable  shade.  The  firm  of  Friedrich  Bayer  &  Co.  employed, 
in  1875,  119  workmen.  The  number  has  more  than  doubled 
itself  every  five  years,  and  in  May  of  this  year  that  firm  employed 
5000  workmen,  160  chemists,  260  engineers  and  mechanics,  and 
680  clerks.  For  many  years  past  it  has  regularly  paid  18  per 
cent,  on  the  ordinary  shares,  which  this  year  has  risen  to  20  per 
cent.  ;  and  in  addition,  in  common  with  other  and  even  larger 
concerns  in  the  same  industry,  has  paid  out  of  profits  for  immense 
extensions  usually  charged  to  capital  account.  There  is  one  of 
these  factories,  the  works  and  plant  of  which  stand  in  the  books 
at  ;£ i, 500,000,  while  the  money  actually  sunk  in  them  approaches 
to  £5,000,000.  In  other  words,  the  practical  monopoly  enjoyed 
by  the  German  manufacturers  enables  them  to  exact  huge  profits 
from  the  rest  of  the  world,  and  to  establish  a  position  which, 
financially  as  well  as  scientifically,  is  almost  unassailable.  I  must 
repeat  that  the  fundamental  discoveries  upon  which  this  gigantic 
industry  is  built  were  made  in  this  country,  and  were  practically 
developed  to  a  certain  extent  by  their  authors.  But  in  spite  of 
the  abundance  and  cheapness  of  the  raw  material,  and  in  spite  of 
the  evidence  that  it  could  be  most  remuneratively  worked  up, 
these  men  founded  no  school  and  had  practically  no  successors. 
The  colours  they  made  were  driven  out  of  the  field  by  newer  and 
better  colours  made  from  their  stuff  by  the  development  of  their 
ideas,  but  these  improved  colours  were  made  in  Germany  and 
not  in  England.  Now,  what  is  the  explanation  of  this  extra- 
ordinary and  disastrous  phenomenon  ?  I  give  it  in  a  word — want 
of  education.  We  had  the  material  in  abundance  when  other 
nations  had  comparatively  little.  We  had  the  capital,  and  we 


APPLIED  CHEMISTRY,  ENGLISH  AND  FOREIGN  225 

had  the  brains,  for  we  originated  the  whole  thing.  But  we  did 
not  possess  the  diffused  education  without  which  the  ideas  of 
men  of  genius  cannot  fructify  beyond  the  limited  scope  of  an 
individual.  I  am  aware  that  our  patent  laws  are  sometimes  held 
responsible.  Well,  they  are  a  contributory  cause  ;  but  it  must 
be  remembered  that  other  nations  with  patent  laws  as  protective 
as  could  be  desired  have  not  developed  the  colour  industry. 
The  patent  laws  have  only  contributed  in  a  secondary  degree, 
and  if  the  patent  laws  have  been  bad  the  reason  for  their  badness 
is  again  want  of  education.  Make  them  as  bad  as  you  choose, 
and  you  only  prove  that  the  men  who  made  them,  and  the  public 
whom  these  men  try  to  please,  were  misled  by  theories  instead 
of  being  conversant  with  fact  and  logic.  But  the  root  of  the 
mischief  is  not  in  the  patent  laws  or  in  any  legislation  whatever. 
It  is  in  the  want  of  education  among  our  so-called  educated 
classes,  and  secondarily  among  the  workmen  on  whom  these 
depend.  It  is  in  the  abundance  of  men  of  ordinary  plodding 
ability,  thoroughly  trained  and  methodically  directed,  that 
Germany  at  present  has  so  commanding  an  advantage.  It  is  the 
failure  of  our  schools  to  turn  out,  and  of  our  manufacturers  to 
demand,  men  of  this  kind,  which  explains  our  loss  of  some 
valuable  industries  and  our  precarious  hold  upon  others.  Let 
no  one  imagine  for  a  moment  that  this  deficiency  can  be  remedied 
by  any  amount  of  that  technical  training  which  is  now  the 
fashionable  nostrum.  It  is  an  excellent  thing,  no  doubt,  but  it 
must  rest  upon  a  foundation  of  general  training.  Mental  habits 
are  formed  for  good  or  evil  long  before  men  go  to  the  technical 
schools.  We  have  to  begin  at  the  beginning  :  we  have  to  train 
the  population  from  the  first  to  think  correctly  and  logically,  to 
deal  at  first  hand  with  facts,  and  to  evolve,  each  one  for  himself, 
the  solution  of  a  problem  put  before  him,  instead  of  learning  by 
rote  the  solution  given  by  somebody  else.  There  are  plenty  of 
chemists  turned  out,  even  by  our  universities,  who  would  be  of 
no  use  to  Bayer  &  Co.  They  are  chock-full  of  formulae,  they 
can  recite  theories,  and  they  know  text-books  by  heart ;  but  put 
them  to  solve  a  new  problem,  freshly  arisen  in  the  laboratory, 
and  you  will  find  that  their  learning  is  all  dead.  It  has  not 
become  a  vital  part  of  their  mental  equipment,  and  they  are 
floored  by  the  first  emergence  of  the  unexpected.  The  men  who 
escape  this  mental  barrenness  are  men  who  were  somehow  or 
other  taught  to  think  long  before  they  went  to  the  university. 

15 


226         THE   BRITISH   COAL-TAR   INDUSTRY 

To  my  mind,  the  really  appalling  thing  is  not  that  the  Germans 
have  seized  this  or  the  other  industry,  or  even  that  they  may 
have  seized  upon  a  dozen  industries.  It  is  that  the  German 
population  has  reached  a  point  of  general  training  and  specialised 
equipment  which  it  will  take  us  two  generations  of  hard  and 
intelligently  directed  educational  work  to  attain.  It  is  that 
Germany  possesses  a  national  weapon  of  precision  which  must 
give  her  an  enormous  initial  advantage  in  any  and  every  contest 
depending  upon  disciplined  and  methodised  intellect. 


XIV.:    1903 

THE  RELATION   BETWEEN   SCIENTIFIC 
RESEARCH  AND  CHEMICAL  INDUSTRY 

BY  PROFESSOR  R.  MELDOLA,  F.R.S. 

(Lecture  delivered  at  the  Oxford  Summer  Meeting,  August  1903) 

THIS  lecture  deals  in  a  general  manner  with  the  interdependence  of 
science  and  industry,  using  as  illustrations  the  manufacture  of  optical 
glass,  fertilisers,  the  fermentation  industries,  and  the  coal-tar  colour 
industry.  The  fundamental  necessity  of  both  pure  and  technical 
research  is  insisted  upon. 


227 


XV.:    1905 

THE    HISTORY  OF  THE   COAL-TAR   COLOUR 
INDUSTRY  BETWEEN   1870  AND   1885 

BY  PROFESSOR  R.  MELDOLA,  F.R.S. 

(Abstract  of  a  Memorandum  which  accompanies  the  Report  of  the 
Committee  on  Industrial  Alcohol  :    Journal  of  the  Society  of  Dyers 
and  Colourists^  1905,  p.  175) 

THE  chief  dyes  made  in  England  during  the  period  1870-1885 
were  magenta,  aniline  blue,  its  sulpho  acids  and  by-products, 
Hofmann  violets,  iodine  green,  Bismarck  brown,  aniline  yellow, 
indulines,  phosphine,  safranine,  chrysoidine,  naphthol  orange 
and  other  azo  dyes,  picric  acid,  Manchester  yellow,  alizarin. 
During  the  same  period  the  dyes  made  abroad,  in  addition  to  the 
above  colouring  matters,  were  methyl  violet,  crystal  violet,  etc. ; 
methylene  blue,  acid  magenta,  malachite  green,  brilliant  green, 
Victoria  blue,  night  blue,  auramine,  etc.  ;  monazo  colours  from 
homologues  of  aniline  and  sulpho  acids  of  naphthols,  disazo 
colours  of  various  kinds,  and  especially  the  direct  cotton  dyes  ; 
oxazines,  such  as  gallocyanine,  etc.  ;  phthalems.  The  decline  in 
our  coal-tar  colour  industry  began  about  the  year  1880.  In  1886 
about  90  per  cent,  of  the  dyes  used  in  England  were  of  foreign 
manufacture.  The  statement  that  the  industry  has  been  driven 
out  of  the  country  for  want  of  duty-free  spirit  is  quite  erroneous, 
because  it  can  be  shown  that  during  the  earlier  years  the  question 
of  the  price  of  alcohol  was  quite  a  subordinate  one.  Our  supre- 
macy had,  in  fact,  been  lost  long  before  the  price  of  alcohol,  as 
compared  with  the  prices  of  the  finished  products,  had  become  a 
matter  of  any  great  importance.  The  cost  of  alcohol  as  a  factor 
in  determining  the  cost  price  of  dyestuffs  could  be  left  out  of 
consideration  altogether,  but  the  further  back  we  go  into  the 
history  of  the  industry,  the  less  important  does  the  price  of 

228 


INFLUENCE   OF   SPIRIT   DUTY  229 

alcohol  become.  It  is  perhaps  fair  to  say  that  during  the  period 
anterior  to  1870  it  was  practically  negligible,  and  during  the 
period  1870-1880  it  was  of  quite  minor  consideration — certainly 
the  relative  cost  of  alcohol  at  that  period  does  not  warrant  the 
belief  that  our  loss  of  the  manufacture  had  anything  to  do  with 
the  spirit  duties. 

Beginning  with  the  home  list.  Hofmann's  violet  and  iodine 
green  are  the  only  dyes  into  the  composition  of  which  the  alcohol 
radical  (methyl)  enters.  They  were  made  from  rosaniline  and 
methyl  iodide,  which  was  then  made  from  wood  naphtha,  and 
was  not  taxed.  None  of  the  other  dyes  on  the  list  required 
alcohol  in  any  quantity  excepting  aniline  blue,  in  which  case  it 
was  used  as  a  solvent.  Methylated  spirit  was  used,  and  after- 
wards recovered  with  little  loss.  The  conclusion  seems  to  be 
inevitable  that  the  spirit  duty  had  nothing  whatever  to  do  with 
the  matter.  Hofmann's  violet  is  now  extinct,  but  aniline  blue 
and  its  derivatives  are  still  important  products,  but  we  have  lost 
our  supremacy,  and  by  far  the  largest  proportion  of  these  dye- 
stuffs  now  on  the  market  is  of  foreign  manufacture.  We  lost 
ground,  therefore,  in  a  branch  of  manufacture  which  was  supreme 
in  this  country,  and  for  which,  although  alcohols  were  required, 
no  excuse  for  our  decadence  could  possibly  have  been  based  on 
the  plea  that  the  spirit  duties  were  to  blame.  Alizarin,  one  of 
the  most  important  products,  was  at  one  time  manufactured  by 
Perkin's  firm  and  their  successors,  and  afterwards  by  the  British 
Alizarin  Company.  Although  the  raw  material  anthracene  is 
produced  in  large  quantities  in  this  country,  the  manufacture  of 
alizarin  here  became  practically  extinct  for  many  years,  although 
it  is  now  being  restored.  Whatever  may  have  been  the  causes 
of  our  temporary  decadence  in  this  case,  the  success  of  our  com- 
petitors cannot  possibly  be  attributed  to  their  command  of  duty- 
free  spirit,  because  alcohol  is  not  used. 

The  proximate  causes  of  our  decadence,  so  far  as  these  are 
concerned  with  the  alcohol  question,  may  be  said  to  be  the  dis- 
covery of  new  colouring  matters  and  processes  by  foreign  chemists, 
and  the  improvement  of  the  processes  for  manufacturing  the  pro- 
ducts already  in  existence.  The  want  of  duty-free  spirit  in  regard 
to  these  improved  processes  cannot  have  been  great  during  the 
period  1 870-1 885.  The  introduction  of  new  dyestuffs  is,  however, 
of  fundamental  importance.  Coming  to  the  foreign  list,  with  the 
exception  of  the  oxazines  all  these  compounds  were  discovered  by 


23o         THE   BRITISH   COAL-TAR   INDUSTRY 

foreign  chemists.  The  author  discovered  the  first  member  of  the 
oxazines  in  1879,  ^ut  ^  was  not  manufactured  here  until  many 
years  later,  and  then  not  in  the  factory  where  it  was  discovered. 
The  manufacture  was  at  once  taken  up  in  Germany.  In  this  case, 
although  one  of  the  raw  materials  contains  the  radical  of  methyl 
alcohol,  the  duty  upon  pure  wood  spirit  had  nothing  to  do  with 
the  transference  of  the  manufacture  of  this  colouring  matter. 

The  introduction  in  1866  of  methyl  violet  (Poirrier)  first 
created  a  demand  for  dimethylaniline  which  contains  the  radical 
methyl.  Dimethylaniline  was  also  necessary  for  methylene  blue 
(1876),  malachite  green  (1878),  crystal  violet,  Victoria  blue,  and 
auramine  (1883).  Diethylaniline  was  necessary  for  brilliant 
green  (1879)  and  night  blue  (1883).  At  the  time,  therefore, 
when  the  decline  of  the  industry  had  seriously  set  in,  with  the 
exception  of  methyl  violet,  none  of  the  dyestufFs  on  the  foreign 
list  were  made  in  this  country,  and  the  dimethyl  and  diethyl- 
anilines  were  being  manufactured  abroad  for  the  manufacture  of 
dyes  discovered  by  foreign  chemists.  The  effect  of  these  newer 
colouring  matters  upon  the  dyestufFs  being  made  here  at  the  time 
of  their  introduction  is  evidently  connected  with  the  loss  of  our 
supremacy.  Hofmann's  violet  was  gradually  replaced  by  methyl 
violet,  and  iodine  green,  which,  however,  was  only  produced  in 
limited  quantity,  was  rapidly  extinguished  by  the  malachite  green 
group.  Victoria  blue  and  methylene  blue  did  not  seriously  inter- 
fere with  our  aniline  blue  group,  as  they  fulfilled  a  different 
function  in  the  tinctorial  industry.  In  1880,  therefore,  the  only 
one  of  our  dyestuffs  directly  affected  by  the  introduction  of  di- 
methylaniline was  Hofmann's  violet.  To  what  extent  did  the 
command  of  duty-free  alcohol  give  our  competitors  an  advantage 
in  the  manufacture  of  such  dyestuffs  as  methyl  violet,  methylene 
blue,  and  malachite  green  ?  They  were  all  foreign  patents.  When 
methyl  violet  was  made  here  the  patent  had  lapsed,  the  dimethyl- 
aniline  being  imported  from  abroad,  as  its  manufacture  was  not 
taken  up  here  down  to  1885,  in  spite  of  Government  concessions 
in  regard  to  duty-free  alcohol  when  the  point  was  first  raised  in 
1880.  Dimethylaniline  can  be  made  by  heating  aniline  hydro- 
chloride  with  pure  methyl  alcohol  in  autoclaves  which  were  used 
on  the  Continent  at  this  time,  but  not  here.  It  can  also  be  made 
by  the  action  of  methyl  chloride,  obtained  in  1878  from  tri- 
methylamine,  a  beet  sugar  by-product,  upon  aniline.  It  there- 
fore could  not  be  produced  cheaply  in  England.  At  that  period 


INFLUENCE   OF   SPIRIT   DUTY  231 

all  the  coal-tar  colours  were  commanding  such  prices  that  the  cost 
of  the  alcohol  was  insignificant  as  compared  with  the  margin  of 
profit.  Methyl  violet  displaced  Hofmann's  violet  because  it  is 
made  directly  from  its  raw  material,  whereas  Hofmann's  violet 
has  to  go  through  several  reactions,  including  the  use  of  methyl- 
iodide. 

With  the  exception  of  methyl  violet,  every  one  of  the  new 
products  necessitated  the  manufacture  of  some  new  raw  material, 
such  as  benzoic  aldehyde  for  malachite  green,  phenylnaphthyl- 
amine  for  Victoria  blue,  tolylnaphthylamine  for  night  blue,  etc. 
None  of  these  raw  materials  required  alcohol  for  their  production. 
The  difference  in  cost  between  the  dyestuffs  made  from  duty-paid 
or  duty-free  alcohol,  as  compared  with  the  margin  of  profit,  was 
quite  insignificant.  During  the  period  dealt  with  our  industry 
was  seriously  affected  by  the  inventive  activity  of  the  foreign 
manufacturers,  but  its  decline  cannot  be  attributed  to  their  having 
the  use  of  duty-free  alcohol. 

The  conditions  have  changed  since  1885.  Prices  were  falling 
from  1880,  and  the  margin  of  profit  becoming  smaller.  The 
difference  in  the  cost  of  manufacture  due  to  the  use  of  duty-free 
spirit  would  now  bear  a  very  much  larger  ratio  to  the  margin  of 
profit,  and  whereas  this  difference  was  formerly  for  all  practical 
purposes  a  negligible  quantity,  it  may  now  have  become  a  serious 
factor.  For  this  reason  the  author's  opinion  is  that  it  is  desirable 
that  our  chemical  manufacturers  should  be  placed  upon  the  same 
footing  as  their  foreign  competitors  so  far  as  concerns  the  use  of 
duty-free  alcohol. 


XVI.:    1906 

NOTE    ON    THE    PERKIN   JUBILEE 

To  mark  the  fiftieth  anniversary  of  the  discovery  of  the  first 
coal-tar  dyestuff  and  as  a  personal  tribute  to  Sir  William  Perkin, 
an  international  meeting  was  held  at  the  Royal  Institution, 
London,  on  Thursday,  26th  July  1906. 

Special  representatives  were  present  from  Germany,  Austria, 
France,  Belgium,  Holland,  Switzerland,  Italy,  Denmark,  Russia, 
and  the  United  States,  in  addition  to  a  very  representative 
gathering  of  British  chemists,  and  a  large  number  of  addresses 
were  presented  to  Sir  William  Perkin  from  British  and  Foreign 
chemical  and  other  societies,  universities,  etc. 

A  further  celebration  was  held  in  the  autumn  of  the  same  year 
when  Sir  William  Perkin  visited  the  United  States. 

Many  interesting  references  dealing  with  the  history  and 
development  of  the  coal-tar  colour  industry  will  be  found  in  the 
speeches  delivered  and  addresses  presented  on  the  occasion  of 
the  London  and  New  York  celebrations,  but  they  cannot  usefully 
be  summarised  here. 

A  full  report  of  the  whole  of  the  proceedings  was  published 
in  book  form  by  the  Perkin  Memorial  Committee  and  issued  by 
The  Times  Office,  London. 


232 


XVII. :    I9o8 
PERKIN    OBITUARY    NOTICE 

BY  PROFESSOR  R.  MELDOLA,  F.R.S. 

(Journal  of  the  Chemical  Society^  1908,  p.  2214) 

THIS  lecture  constitutes  the  Obituary  Notice  of  Sir  William  Perkin 
contributed  to  the  Chemical  Society.  It  gives  a  complete  review  of 
Perkin  s  life  and  work,  but  the  points  of  especial  interest  from  the 
point  of  view  of  the  present  work  are  largely  covered  by  the  following 
papers : — 

Perkin  :    "  The  Colouring  Matters  produced  from   Coal-tar" 

t;  75- 
Perkin :    "  The    Origin   of  the    Coal-tar    Colour  Industry" 

p.  141. 

Meldola  :  "  The  Founding  of  the  Coal-tar  Colour  Industry" 
P-  234. 


233 


XVIII. :    I9o8 

THE  FOUNDING  OF  THE  COAL-TAR 
COLOUR  INDUSTRY 

BY  PROFESSOR  R.  MELDOLA,  F.R.S. 

(Presidential  Address  to  the  Society  of  Dyers  and  Colourists,  1908  : 
Journal  of  the  Society  of  Dyers  and  Colour  ists^  1908,  p.  95) 

THE  late  President  of  the  Society,  Sir  William  Henry  Perkin, 
passed  away  on  i/j-th  July  1907,  in  the  sixty-ninth  year  of  his 
age,  and  in  the  zenith  of  his  fame.  It  would  be  superfluous  to 
retell  here  the  story  of  the  discovery  of  mauve,  or  the  influence 
of  that  discovery  upon  the  tinctorial  industries.  The  great  inter- 
national gathering  of  1906,  which  will  still  be  fresh  in  your 
memories,  furnished  ample  opportunity  for  reviewing  the  life- 
work  of  the  man  whom  the  nations  had  assembled  to  honour, 
and  he  himself  gave  a  very  full  account  of  his  connection  with 
the  industry.  This  is  all  recorded  in  the  official  report  of  the 
jubilee  meeting  published  by  the  Memorial  Committee.  Some 
interesting  reminiscences  were  also  given  by  Sir  Robert  Pullar 
and  others  at  last  year's  annual  dinner,  at  which  Sir  William 
Perkin  presided,  and  of  which  a  full  report  was  published  in  the 
April  number  of  the  Journal.  I  have,  moreover,  written  an 
obituary  notice  of  him  for  the  Royal  Society,  and  in  this  I  have 
endeavoured  to  do  justice  to  his  scientific  work  and  personal 
character.  It  cannot  but  be  a  source  of  the  greatest  satisfaction 
to  us  all — the  one  mitigating  circumstance  that  lightens  our 
sorrow  at  his  loss — that  he  fell  from  our  ranks  not  unrecognised, 
as  is  the  fate  of  so  many  of  our  scientific  pioneers  in  this  country, 
but  laden  with  freshly  bestowed  honours,  and  with  the  full 
knowledge  that  his  labours  had  won  lasting  gratitude  in  the  two 
great  spheres  of  human  activity,  Science  and  Industry.  Further- 

234 


THE   FOUNDING   OF   THE   INDUSTRY        235 

more,  it  cannot  but  be  a  gratifying  memory  to  us  that  our 
Society  throughout  its  future  history  will  be  able  to  point  to  the 
name  of  Perkin  on  the  roll  of  its  past  Presidents.  He  died  in 
our  service,  and  one  of  his  last  acts  in  connection  with  this 
Society  was  to  accompany  the  deputation  to  the  Dyers'  Company 
in  order  to  plead  with  that  worshipful  body  for  assistance  in 
founding  prizes  to  be  awarded  by  our  Society  for  the  solution  of 
technical  problems  connected  with  the  industry. 

On  the  present  occasion  our  annual  gathering,  saddened  by 
the  loss  of  our  late  President,  will  be  made  memorable  by  its 
marking  the  first  award  of  the  Perkin  medal,  founded  in  1906 
in  celebration  of  the  jubilee  of  the  discovery  and  manufacture 
of  the  first  coal-tar  colouring  matter.  No  more  fitting  tribute 
to  the  memory  of  my  distinguished  predecessor  could  be  paid 
than  that  his  successor  in  this  chair  should  endeavour  to  enable 
you  to  realise  the  full  measure  of  our  indebtedness  to  him.  I 
propose  therefore  to  invite  you  to  take  with  me  a  retrospective 
glance  into  the  conditions,  scientific  and  industrial,  antecedent  to 
that  accidental  discovery  of  1856,  which  marked  the  beginning 
of  the  modern  revolution  in  all  tinctorial  methods.  Let  us  con- 
sider, in  the  first  place,  the  state  of  affairs  with  respect  to  the  raw 
materials  required  for  the  manufacture  of  mauve.  These  were 
benzene,  nitrobenzene,  and  aniline. 

Benzene,  as  you  are  aware,  was  discovered  by  Michael  Faraday, 
in  1825,  as  a  component  of  the  liquid  obtained  by  the  compression 
of  oil-gas.  Twenty  years  later  Hofmann  found  this  hydrocarbon 
in  coal-tar,  and  proved  its  presence  by  preparing  from  it  nitro- 
benzene and  aniline,  the  latter  being  identified  by  the  usual  tests. 
The  occurrence  of  benzene  in  coal-tar  was  thus  known  in  1 845, 
and  in  1 848  one  of  Hofmann's  brilliant  young  students  at  the 
Royal  College  of  Chemistry,  Charles  Blachford  Mansfield,  at  the 
instigation  of  his  illustrious  master,  undertook  a  systematic  study 
of  coal-tar,  with  a  view  to  the  isolation  and  identification  more 
especially  of  the  "  neutral  liquid  oils,"  of  which  he  tells  us  in  his 
paper  published  by  the  Chemical  Society  in  1 849  we  had  at  that 
time  "  no  precise  information."  When  Mansfield  took  up  this 
work  a  few  definite  compounds  were  known  to  exist  in  this  tar, 
notably  naphthalene,  which  had  been  isolated  by  Garden  in  1820, 
and  certain  acid  and  basic  substances,  such  as  phenol  (carbolic 
acid),  aniline  (kyanol),  quinoline  (leucol  or  leucoline),  and  pyrole, 
all  of  which  had  been  isolated  by  Runge  in  1834.  Anthracene, 


236         THE   BRITISH   COAL-TAR   INDUSTRY 

under  the  name  of  "  paranaphthaline,"  was  isolated  by  Dumas 
and  Laurent  in  1833,  although  it  is  now  known  that  their  original 
analysis,  which  assigned  to  this  hydrocarbon  15  atoms  of  carbon, 
was  erroneous.  Chrysene  and  pyrene  had  also  been  indicated, 
but  only  superficially  studied  by  Laurent  in  1837.  To  the  basic 
constituents  picoline  was  added  in  1846  by  Anderson. 

Such  was  the  state  of  knowledge  when  Hofmann  set  Mansfield 
to  work  upon  the  coal-tar  hydrocarbons.  The  paper  embodying 
his  results  is  entitled  "  Researches  on  Coal  Tar,  Part  I.,"  x  and 
now,  nearly  sixty  years  after  its  publication,  it  can  still  be  read  with 
interest  and  profit.  Its  contents  have  become  historic  in  con- 
nection with  the  colour  industry,  and  must  rank  with  Runge's 
celebrated  papers  of  i8342  among  the  most  important  con- 
tributions to  tar  chemistry  that  preceded  the  foundation  of  that 
industry. 

Even  at  the  time  of  Mansfield's  work  no  coal-tar  hydrocarbon 
had  been  utilised  as  a  source  of  other  chemical  compounds, 
tinctorial  or  otherwise,  and  he  himself,  in  describing  the  practical 
applications  of  benzene,  refers  only  to  its  use  as  a  solvent  or  an 
illuminant.  Perkin's  discovery  thus  created  a  demand  for  this 
hydrocarbon  as  a  raw  material  in  a  new  industry  on  a  scale  never 
before  contemplated.  Mansfield's  experiments  had  prepared 
the  way,  but  there  had  been  no  demand  for  benzene,  and  the 
tar  distillers  could  not  at  first  supply  it  in  quantity  or  in  a 
sufficient  state  of  purity.  It  is  of  interest  to  know  that  the 
first  supply  of  this  material  used  by  Perkin  came  from  the  Scotch 
tar  distillery  of  Messrs  Miller  &  Co.,  of  Glasgow. 

Then  came  the  difficulties  connected  with  the  nitration  and 
the  reduction  of  the  nitrobenzene  to  aniline.  Here  again 
Mansfield  had  played  the  part  of  a  pioneer,  but  his  process 
was  impracticable  on  the  scale  now  required.  Moreover,  it 
was  too  costly,  for  it  must  be  borne  in  mind  that  the  new  dye 
had  to  compete  with  the  existing  vegetable  colouring  matters, 
and  on  I2th  June  1856,  Messrs  Pullar,  of  Perth,  who  had 
been  testing  the  dyeing  properties  of  mauve,  had  reported  to 

1  Chem.  Soc.   Quart.  Jour.,  1849,  vol.  i.  p.  244.      He  gave  a   general 
account  of  his  work  at  a  Friday  evening  discourse  at  the  Royal  Institution 
on  2yth  April  1849,  which  was  published  as  a  brochure,  entitled  "Benzole: 
its  Nature  and  Utility." 

2  Poggendorff's  A nnalen,  vol.  xxxi.  pp.  65  and  513;  vol.  xxxii.  pp.  308 
and  328. 


THE   FOUNDING   OF   THE   INDUSTRY        237 

Perkin  that  the  discovery  was  a  valuable  one  provided  it  did  not 
"  make  the  goods  too  expensive."  It  is  needless  to  say  that 
nitric  acid  of  the  strength  used  by  Mansfield  would  have  been 
a  very  costly  material  in  1856.  In  fact,  nitric  acid  of  sufficient 
strength  to  nitrate  benzene  could  not  be  obtained  in  quantity 
at  that  period,  and  Perkin  had  to  devise  apparatus  for  nitrating 
with  a  mixture  of  sulphuric  acid  and  sodium  nitrate.  His 
resourcefulness  is  well  revealed  by  this  passage  quoted  from  his 
Hofmann  Memorial  Lecture  in  1876  : — "At  this  time  neither 
I  nor  my  friends  had  seen  the  inside  of  a  chemical  works,  and 
whatever  knowledge  I  had  was  obtained  from  books.  This, 
however,  was  not  so  serious  a  drawback  as  at  first  it  might 
appear  to  be,  as  the  kind  of  apparatus  required,  and  the  character 
of  the  operations  to  be  performed,  were  so  entirely  different  from 
any  in  use  that  there  was  but  little  to  copy  from. 

"  In  commencing  this  manufacture  it  was  absolutely  neces- 
sary to  proceed  tentatively,  as  most  of  the  operations  required 
new  kinds  of  apparatus  to  be  devised  and  tried  before  more 
could  be  ordered  to  carry  out  the  work  on  any  scale "  (see 
p.  153,  ante). 

After  the  manufacture  of  mauve  had  been  started  the 
demand  for  the  new  dyestufF  increased  to  such  an  extent  that 
the  resources  of  the  Greenford  factory  were  taxed  to  their 
utmost,  and  the  assistance  of  another  firm  had  to  be  called  in 
for  supplying  raw  materials.  That  firm  was  Simpson,  Maule  & 
Nicholson,  whose  factory  was  at  Locksfields,  in  the  south  of 
London.  The  Nicholson  of  the  firm  was  that  pupil  of  Hofmann's 
already  referred  to  as  having  been  a  co-worker  with  Mansfield, 
and,  under  his  energetic  management,  they  not  only  supplied 
the  firm  of  Perkin  &  Sons  with  some  of  the  raw  materials 
required,  but  later  they  also  entered  the  colour  industry,  and 
in  1865  established  the  Atlas  Works  at  Hackney  Wick,  the 
firm  being  transferred  in  1868  to  Messrs  Brooke,  Simpson  & 
Spiller.  Mr  William  Spiller,  formerly  of  this  latter  firm,  has 
told  me  that  he  well  remembers  the  early  stages  in  the 
manufacture  of  nitrobenzene  by  their  predecessors  at  Locksfields, 
where  he  was  then  working  in  association  with  the  late 
Mr  E.  C.  Nicholson.  The  nitration  was  carried  out  in  large 
glass  "  boltheads "  arranged  in  series,  as  they  had  not  then 
discovered  that  cast-iron  vessels  could  be  used.  The  scale  of 
working  was  quite  small  as  compared  with  the  modern  output 


238         THE   BRITISH   COAL-TAR   INDUSTRY 

from  a  large  nitrating  still,  and  they  experienced  the  difficulty 
referred  to  by  Perkin  of  obtaining  a  supply  of  pure  benzene. 
The  operation  also  was  somewhat  capricious,  owing  to  the  want 
of  uniformity  in  the  quality  of  the  commercial  "  benzole," 
and  to  the  absence  of  mechanical  stirring.  The  cheapening 
of  the  process  by  the  introduction  of  cast-iron  stills  with 
mechanical  stirring  gear  did  not  take  place  until  some  time  after 
the  manufacture  of  mauve  had  been  commenced  in  1857.  The 
plant  in  use  was  described  and  figured  by  Perkin  in  his  Cantor 
Lectures,  delivered  before  the  Society  of  Arts  in  1868,  and  has 
since  been  refigured  in  many  works  on  technology,  as  it  is 
practically  the  same  in  principle  as  that  now  generally  in  use.1 

The  next  step,  the  reduction  to  aniline,  had  also  to  be 
worked  out  on  the  manufacturing  scale.  The  laboratory  method 
then  generally  in  use  was  Zinin's,  viz.  sulphuretted  hydrogen 
in  presence  of  ammonia,  a  process  obviously  impracticable  on 
the  large  scale.  The  use  of  metals,  such  as  tin  or  zinc,  in 
combination  with  acids,  would  have  been  both  costly  and 
unmanageable.  Fortunately,  however,  Bechamp  in  1854  had 
found  that  iron  and  acetic  acid  could  be  used  for  reducing 
nitro  compounds,  and  Perkin,  who  had  been  familiarised  with 
this  process  in  Hofmann's  laboratory,  applied  it  successfully  for 
the  manufacture  of  aniline.2  That  this  was  a  task  of  considerable 
difficulty  can  be  readily  understood  by  those  who  are  familiar 
with  the  violence  of  such  "  reducing  "  processes,  unless  properly 
controlled.  It  is,  in  fact,  known  that  at  first  serious  attempts 
were  made  to  extract  the  minute  quantity  of  aniline  contained 
in  the  coal-tar  oils  directly  by  acid  washing — a  process  which, 
it  is  needless  to  say,  had  soon  to  be  abandoned  on  account  of 
its  cost  and  the  impure  state  of  the  product.  In  the  manufacture 
of  aniline  from  nitrobenzene  the  firm  of  Simpson,  Maule  & 
Nicholson  also  co-operated  with  Perkin  &  Sons,  and  Mr 
William  Spiller  has  given  me  a  graphic  description  of  their 

1  A  workman,  James  Underwood,  in  the  employment  of  Simpson,  Maule 
&  Nicholson,  at  Locksfields,  during  the  early  years  of  the  colour  industry, 
also   remembers  this  manufacture   of    nitrobenzene   in   boltheads  and   the 
development   to   cast-iron  stills.     This  last  improvement  is  generally  attri- 
buted to  E.  C.  Nicholson.      A  figure  of  the  earliest  form  of  (horizontal) 
still  was  given  by  Perkin  in  his  Cantor  Lectures  above  referred  to. 

2  "  Had  it  not  been  for  this  discovery  the  coal-tar  colour  industry  could 
not  have  been  started." — W.  H.  Perkin,  Hofmann  Memorial  Lecture  (see 
p.  153,  ante). 


THE   FOUNDING   OF  THE   INDUSTRY        239 

early  work  at  Locksfields  when  starting  this  branch  of  the 
industry.  The  reduction  was  carried  out  in  iron  vessels  with 
removable  still-heads,  the  vessel  being  at  first  uncovered,  and 
the  materials,  nitrobenzene,  iron  turnings,  and  acetic  acid,  simply 
stirred  up  by  a  rod  until  the  reaction  showed  signs  of  starting. 
The  still-head  was  then  immediately  clapped  on,  and  a  workman 
mounted  guard  with  water-hose  ready  to  play  over  the  still  if 
the  contents  gave  signs  of  boiling  too  violently.  The  cost  of 
the  acetic  acid  was  a  considerable  item  at  that  time,  and  they 
had  to  make  their  own  acid  by  heating  sodium  acetate  with 
sulphuric  acid.  It  was  soon  found  that  hydrochloric  acid  could 
be  used  instead  of  acetic  acid,  and  the  introduction  of  stills 
with  mechanical  stirrers  put  this  branch  of  the  manufacture  on 
a  sure  basis.  It  is  perhaps  hardly  necessary  to  point  out  that 
the  "aniline"  of  that  period  was  a  mixture  of  homologues,  and 
very  impure  from  the  modern  point  of  view. 

And  so  the  manufacture  of  the  first  of  the  "synthetic 
dyestuffs  "  was  started  at  Greenford  Green  towards  the  end  of 
the  year  1857,  and  the  genius  of  the  founder  had  ample  scope 
for  exercise.  Let  it  be  borne  in  mind  that  the  raw  product 
obtained  by  oxidising  crude  aniline  with  sulphuric  acid  and 
potassium  dichromate  was  what  would  now  be  called  a  "  resinous 
mess."  Processes  for  its  purification  had  to  be  devised,  and 
here  again  the  resourcefulness  of  Perkin  becomes  manifest. 
With  that  true  scientific  spirit  which  dominated  all  his  work 
the  investigation  of  his  products  and  processes  was  always  kept 
going.  At  first  the  crude  product  was  collected  on  filters  and 
washed  with  water  to  remove  excess  of  aniline  sulphate,  then 
dried  and  powdered,  and  extracted  with  coal-tar  "  naphtha " 
until  free  from  resinous  impurities,  then  dried  again  and 
extracted  with  methylated  spirit,  and  the  filtered  solution  distilled 
until  the  dyestufF  separated  out.  This  method  of  purification 
was  afterwards  improved  and  cheapened  by  the  omission  of  the 
naphtha  treatment,  as  it  was  found  that  diluted  methylated 
spirit  extracted  the  colouring  matter  directly,  and  left  the  resin 
undissolved.  The  process  was  finally  simplified  by  boiling  out 
the  colouring  matter  with  water  alone,  and  precipitating  with  an 
alkali  so  as  to  obtain  the  free  base,  which  was  then  converted 
into  acetate  for  use  by  the  dyers. 

The  discovery  and  manufacture  of  mauve,  with  its  train  of 
consequences,  must  be  regarded  as  constituting  but  a  portion  of 


24o         THE   BRITISH    COAL-TAR   INDUSTRY 

Perkin's  claim  to  our  gratitude.  In  starting  upon  this  work  he 
had,  against  the  advice  of  his  illustrious  master,  Hofmann, 
broken  away  from  the  path  of  pure  science  and  entered  a  field 
in  which  he  was  a  novice.  His  whole  future  was  bound  up  with 
the  success  of  the  undertaking,  for  his  father  had  placed  nearly 
his  entire  capital  in  the  venture  in  order  to  establish  the  factory 
at  Greenford  Green.  There  was  evidently  something  more  to 
be  done  besides  placing  the  new  dyestuff  on  the  market.  The 
dyers  and  printers  had  to  be  convinced  of  its  merits  and  taught 
how  to  use  it.  This  task,  by  no  means  a  light  one,  had  also  to 
be  undertaken  by  Perkin,  who,  up  to  that  time,  had  never  been 
brought  into  contact  with  the  tinctorial  industries.  It  has  fre- 
quently been  mentioned  that  Messrs  Pullar,  of  Perth,  were  the 
first  to  give  encouragement  to  the  young  inventor  so  far  as 
concerned  the  dyeing  properties  of  mauve.  At  their  instigation 
it  was  tried  for  silk  dyeing  by  Thomas  Keith,  silk  dyer,  of 
Bethnal  Green,  London,  and  he  also  reported  favourably.  But, 
as  is  generally  the  case  with  new  departures,  the  step  from  the 
experimental  to  the  practical  scale  was  not  made  without  en- 
countering difficulties.  It  was  found  that  on  the  large  scale 
the  dye  "  took  on  "  unevenly,  and  caused  a  patchy  appearance, 
so  that  a  restraining  material  had  to  be  added  to  the  bath.  The 
use  of  the  soap  bath  for  silk  dyeing  was  the  outcome  of  Perkin's 
association  with  a  practical  dyer,  and  Keith's  dyehouse  was  the 
first  in  which  mauve  was  used  on  the  industrial  scale. 

Then  with  respect  to  wool  and  cotton  dyeing,  the  same 
pioneering  work  had  to  be  done.  Perkin  has  told  us  that  he 
and  Mr  (now  Sir)  Robert  Pullar  had  independently  discovered 
the  use  of  tannin  and  a  metallic  oxide  as  a  mordant  for  cotton 
dyeing,  and,  in  conjunction  with  Alexander  Schultz,  he  had 
introduced  the  "  insoluble  arsenite  of  alumina "  as  a  mordant. 
The  calico  printers  in  this  country  did  not  at  first  take  kindly  to 
the  new  colouring  matter,  and  Perkin  has  often  told  me  that 
the  impetus  to  this  most  important  application  of  his  discovery 
came  from  France.  It  appears  that,  owing  to  some  technical 
oversight,  the  French  patent  was  ineffective,  and  the  French 
manufacturers  accordingly  began  making  the  new  dyestuff  them- 
selves. It  was  in  France,  in  fact,  that  the  term  "  mauve  "  was 
given.  With  the  well-known  skill  of  the  French  calico  printers 
beautiful  designs  in  mauve  were  produced  and  sent  over  to  this 
country,  and  this  was  more  effective  than  any  other  cause  in 


THE   FOUNDING   OF   THE   INDUSTRY        241 

hastening  the  use  of  the  dye  for  this  purpose  over  here.  Had 
it  not  been  for  this  stimulus  the  success  of  the  new  factory  would 
have  been  doubtful,  for  Messrs  Pullar  had  reported  to  Perkin  that, 
in  their  opinion,  unless  the  new  dye  could  be  used  by  the  printers 
it  would  be  questionable  whether  "  it  would  be  wise  to  erect  works 
for  the  quantity  dyers  alone  will  require."  l  In  summing  up  this 
part  of  his  experience  Perkin  stated  in  1896  : — 

"  Before  the  aniline  purple  could  be  introduced  for  dyeing 
woollen  and  mixed  fabrics,  some  weeks  were  also  spent  at 
Bradford  in  rinding  out  suitable  methods  of  applying  it. 

"  Thus  it  will  be  seen  that,  in  the  case  of  this  new  colouring 
matter,  not  only  had  the  difficulties  incident  to  its  manufacture 
to  be  grappled  with,  and  the  prejudices  of  the  consumer  over- 
come, but,  owing  to  the  fact  that  it  belonged  to  a  new  class 
of  dyestuffs,  a  large  amount  of  time  had  to  be  devoted  to  the 
study  of  its  applications  to  dyeing,  calico  printing,  etc.  It  was, 
in  fact,  all  pioneering  work — clearing  the  road,  as  it  were,  for 
the  introduction  of  all  colouring  matters  which  followed,  all 
the  processes  worked  out  for  dyeing  silk,  cotton,  and  wool, 
and  also  for  calico  printing,  afterwards  proving  suitable  for 
magenta,  Hofmann  violet,  etc."  (Hofmann  Memorial  Lecture, 
loc.  cif.,  p.  609.) 

It  will  be  remembered  that  at  our  last  anniversary  dinner, 
presided  over  by  Perkin,  Sir  Robert  Pullar  gave  us  some  of 
his  early  reminiscences  concerning  the  attitude  of  the  Scotch 
calico  printers  towards  the  new  colouring  matter. 

The  success  of  the  new  industry  had  for  its  natural  con- 
sequence the  creation  of  a  host  of  imitators.  All  kinds  of 
oxidising  agents  were  tried  upon  aniline  and  made  the  subjects 
of  rival  patents.  The  departure  from  the  original  patent  was 
in  some  cases  so  slight  that  it  is  questionable  whether  in  modern 
patent  legislation  the  inventor's  claim  would  not  be  dismissed  as 
a  "  colourable  imitation."  Tabourin  and  Franc  Bros,  claimed 
aniline  hydrochloride  instead  of  sulphate  ;  Beale  and  Kirkham 
in  England,  as  well  as  Scheurer-Kestner,  Depouilly  and  Lauth, 
Coblentz,  and  C.  Phillips  in  France,  claimed  bleaching  powder  ; 

1  "  I  distinctly  remember,  the  first  time  I  induced  a  calico  printer  to 
make  trials  of  this  colour,  that  the  only  report  I  obtained  was  that  it  was  too 
dear,  and  it  was  not  until  nearly  two  years  afterwards,  when  French  printers 
put  aniline  purple  into  their  patterns,  that  it  began  to  interest  English 
printers." — Perkin's  Cantor  Lectures,  Society  of  Arts  (see  p.  15,  ante). 

16 


242         THE   BRITISH   COAL-TAR   INDUSTRY 

Smith  claimed  chlorine  water,  Greville  Williams  potassium  per- 
manganate, Kay  manganese  dioxide,  David  Price  (attached  to 
the  firm  of  Simpson,  Maule  &  Nicholson)  claimed  lead 
peroxide,  Dale  and  Caro  cupric  chloride,  Stark  and  Guyot 
red  prussiate  of  potash,  and  so  forth.  It  is  needless  to  point 
out  that  many  of  the  products  obtained  by  these  inventors 
could  not  have  been  Perkin's  mauve  at  all,  and,  as  a  matter 
of  fact,  not  one  of  these  rival  processes  was  enabled  to  com- 
pete successfully  with  the  original  "  bichromate  "  method.  The 
yield  was  too  small,  or  the  colour  too  difficult  to  purify,  or 
the  oxidising  agent  too  expensive,  although  at  that  time  the 
bichromate  cost  from  icd.  to  nd.  per  pound.  The  only  one 
of  these  processes  which  gave  a  good  result  was  Dale  and 
Caro's,  but  even  this  could  not  be  worked  so  economically  as 
the  original  process. 

The  introduction  of  mauve  by  the  founder  of  and  pioneer 
in  this  new  development  in  manufacturing  chemistry  soon  led, 
as  you  are  all  aware,  to  the  further  discovery  of  coal-tar  colouring 
matters  and  to  the  establishment  of  other  factories.  My  present 
theme  centres  round  Perkin's  work  in  this  field,  and  I  do  not 
propose  to  enlarge  upon  the  discoveries  of  others  excepting  in 
so  far  as  they  influenced  the  life  of  our  late  President.  For 
about  a  decade  the  manufacturing  operations  at  Greenford  were 
carried  on  successfully,  and  without  any  fresh  discovery  of  very 
great  importance,  although  Perkin's  activity  in  the  field  of  pure 
scientific  investigation  never  ceased.  Magenta  was  first  made 
industrially  by  Verguin,  in  France,  in  1859,  and  the  firm  of 
Simpson,  Maule  &  Nicholson  soon  began  to  manufacture  this 
on  the  large  scale  by  the  arsenic  acid  process  as  well  as  other 
well-known  colouring  matters.  Such  was  the  development  of 
the  industry  that  in  1862,  the  year  of  the  International  Exhibition 
in  London,  Hofmann  gave  a  Friday  evening  discourse  at  the 
Royal  Institution,1  from  which  it  appears  that  the  definite  com- 
pounds which  had  been  isolated  from  coal-tar,  and  which  in 
Mansfield's  lists  of  1 848  consisted  of  thirteen,  had  then  risen  to 
about  forty.  It  was  for  that  Exhibition  that  Messrs  Simpson, 
Maule  &  Nicholson  prepared  a  crown  of  magenta  crystals 
(acetate),  which  Hofmann  exhibited  during  his  lecture,  the  title 
of  which  was  "  Mauve  and  Magenta."  The  selling  price  of  the 
new  dyes  at  that  time  may  be  gathered  from  the  circumstance 
1  Chemical  News,  vol.  vi.  p.  90. 


THE   FOUNDING   OF  THE   INDUSTRY       243 

that  the  purified  solid  mauve  sold  for  about  the  same  price  as 
platinum,  weight  for  weight,  and  the  vat  from  which  the 
magenta  cc  crown "  had  been  crystallised  contained  a  weight  of 
the  acetate  of  that  base  valued  at  j£8ooo,  the  crystals  adhering 
to  the  wire  framework  of  the  crown  being  valued  at  ^roo.1 

The  discovery  and  manufacture  of  magenta  was  undoubtedly, 
after  the  production  of  mauve,  the  most  important  contribution 
to  the  industry  made  during  the  decade  referred  to.  This  dis- 
covery did  not  at  first  affect  Perkin's  operations  ;  mauve  still 
held  its  own,  and  in  1859  Perkin's  brother  Thomas,  the 
business  man  of  the  establishment,  patented  on  behalf  of  the 
firm  a  process  for  making  magenta  by  oxidising  crude  aniline 
with  mercuric  nitrate.2  This  was  an  improvement  upon  the 
original  stannic  chloride  process  of  Verguin,  but  it  was 
dangerous,  capricious,  and  expensive,  and  was  very  soon  dis- 
placed by  Medlock's  arsenic  acid  process  worked  by  Simpson, 
Maule  &  Nicholson,  and  also,  as  the  result  of  a  celebrated 
lawsuit,  by  Messrs  Read  Holliday  &  Sons,  of  Huddersfield. 
But  although  Perkin  &  Sons  never  made  magenta  in  any 
quantity,  the  introduction  of  this  dyestuff  led  to  new  and 
necessary  developments  in  their  factory.  About  five  years  after 
the  foundation  of  the  Greenford  works,  Hofmann,  who  had 
then  enthusiastically  entered  the  field  of  colour  chemistry,  found 
that  magenta  when  ethylated  or  methylated  gave  rise  to 
violet  colouring  matters,  the  manufacture  of  which  was  at  once 
taken  up  by  Simpson,  Maule  &  Nicholson.3  Hofmann's  violets 
and  certain  phenylated  rosanilines,  discovered  about  the  same 
time  by  Girard  and  De  Laire,  in  France,  and  made  here  also  by 
Simpson,  Maule  &  Nicholson,  soon  began  to  enter  into  com- 
petition with  mauve. 

1  Some  of  the  original  crystals  are  now  in  the  possession  of  Mr  William 
Spiller.      A  trade  catalogue  of  the  firm  of  Simpson,   Maule  &  Nicholson, 
placed  at  my  disposal  by  Dr  Cain,  shows  that  in  1866  "pure  roseine"  was 
priced  at  25.  6d.  per  oz. 

2  "  Das  Zinnchlorid  wird  durch  das  Quecksilbernitrat  ersetzt,  mit  dem 
die  Fabrikation  auch  in  Deutschland  ihre  ersten,  kraftigen  Wurzeln  fasst." — 
H.  Caro,  JBer.,  1892,  p.  1031. 

3  The  manufacture  of  methyl  and  ethyl  iodide  on  the  large  scale  was  a 
remarkable  achievement  at  the  time.     When  I  entered  the  Atlas  Works,  in 
1877,  the  Hofmann  violets  were  still  being  manufactured,  and  the  use  of 
these  colouring  matters  by  English  dyers  continued  for  more  than  twenty 
years  after  that  date.     The  violet  is  priced  in  the  1866  catalogue  of  Simpson, 
Maule  &  Nicholson  at  35.  per  oz. 


244         THE   BRITISH   COAL-TAR   INDUSTRY 

It  has  not,  1  think,  been  sufficiently  dwelt  upon  by  any  of  the 
historians  of  the  coal-tar  colour  industry  that  Perkin' s  pioneering 
discovery  reacted  upon  itself,  for  there  can  be  no  doubt  that  the 
production  of  aniline  on  the  large  scale  led  to  the  discovery  of 
processes  for  the  manufacture  of  magenta,  and  it  was  the 
derivatives  of  the  latter  that  first  began  seriously  to  displace 
mauve.  The  discovery  by  Lauth  of  colouring  matters  such  as 
methyl  violet,  formed  by  the  oxidation  of  the  alkylated  anilines 
and  manufactured  in  France  about  1866,  brought  into  the  field 
other  competitors  with  the  original  mauve.  The  newer  dyes  were 
not  so  fast  as  mauve,  but  they  were  much  more  brilliant,  and 
fastness  soon  gave  way  to  brightness.  The  practical  effect  of 
these  later  developments  made  itself  felt  in  the  gradual  decline 
in  the  demand  for  mauve,  the  use  of  which  soon  became  very 
limited,  and  finally  died  out  altogether.  As  a  flourishing  branch 
of  the  colour  industry  it  may  be  said  that  mauve  did  not  com- 
plete ten  years  of  its  existence.  But  Perkin  was  enabled  to 
keep  the  Greenford  works  going  successfully  in  spite  of  the 
adverse  influence  of  the  new  discoveries  and  the  coming  into 
existence  of  other  factories.  He  introduced  in  1864  a  very 
ingenious  method  for  the  indirect  alkylation  of  magenta,  which 
enabled  their  firm  to  compete  with  the  other  violet  colouring 
matters  then  in  the  market.  This  method  consisted  in  heating 
magenta  base  with  methylated  spirit — afterwards  improved  by 
substituting  methyl  alcohol — and  the  compound  formed  from 
turpentine-oil  and  bromine  in  the  presence  of  water.  This 
"  brominated  turpentine "  had  long  been  known  to  chemists, 
and  had  been  investigated  by  Greville  Williams,  but  had  never 
before  been  used  for  manufacturing  purposes.  The  dyes  thus 
made  were  introduced  under  name  of  Britannia  violet  of  different 
shades  of  blueness,  according  to  the  degree  of  alkylation.  It 
was  at  first  thought  that  they  contained  the  terpene  radicle, 
although  it  was  afterwards  considered  that  they  were  of  the 
same  type  as,  if  not  identical  with,  the  Hofmann  violets,  so  that 
Perkin  had  really  discovered  an  indirect  method  of  methylation 
of  a  type  unknown  in  chemistry  at  that  time.  Perkin's  process 
was  very  successful,  although  he  was  handicapped  by  having  to 
purchase  magenta  base,  which  his  firm  did  not  manufacture. 
But,  on  the  other  hand,  brominated  turpentine  was  cheaper  as  an 
alkylating  agent  than  the  methyl  iodide  used  in  the  manufacture 
of  Hofmann  violets. 


THE   FOUNDING   OF  THE   INDUSTRY        24$ 

I  will  venture  to  interpolate  here  a  small  experience  of  my 
own,  because  it  is  connected  with  this  same  department  of  the 
colour  industry,  and,  although  the  experiments  which  I  am  about 
to  describe  were  carried  out  thirty-seven  years  ago,  I  have  never 
had  such  a  favourable  opportunity  for  placing  them  upon  record. 
The  violet  dyes  now  known  to  be  alkylated  rosanilines  were  at  that 
time  being  sold  at  very  high  prices,  and  any  new  process,  i.e. 
any  process  which  did  not  infringe  existing  patents,  would  have 
been  of  very  great  commercial  value.  As  a  youth  I  had  just 
then  entered  the  colour  industry  in  the  service  of  Messrs 
Williams,  Thomas  &  Dower,  of  the  Star  Chemical  Works, 
Brentford.  In  1870  it  occurred  to  me,  in  view  of  Perkin's 
success  with  brominated  turpentine,  to  try  whether  the  additive 
compounds  of  defines  with  bromine  were  equally  effective,  and 
my  first  experience  in  manufacturing  chemistry  was  the  produc- 
tion of  ethylene  bromide  on  the  large  scale.  This  part  of  the 
process  was  very  successfully  carried  out,  and  I  have  a  very 
vivid  recollection  of  the  pride  with  which  I  displayed  ethylene 
bromide  in  Winchester  quart  bottles,  the  compound  being 
obtained  in  almost  quantitative  yield  by  passing  ethylene  from 
alcohol  and  sulphuric  acid  through  bromine  in  a  special  form  of 
apparatus  which  I  devised  for  this  operation.  But,  alas  !  the 
next  part  of  the  process  proved  a  failure.  The  ethylene  bromide 
did  react  with  the  magenta  base  in  presence  of  methyl  alcohol, 
but  the  alkylene  radicle  itself  entered  the  rosaniline  molecule — 
there  was  no  transference  of  radicle  as  in  Perkin's  process,  and 
the  ethylenerosaniline  turned  out  to  be  an  insoluble  resin  of  no 
use  as  a  dyestuff.  Fuming  sulphuric  acid  might  possibly  have 
saved  the  situation,  but  this  was  before  the  days  of  "acid 
magenta,"  and  nobody  then  knew  that  such  compounds  could 
be  sulphonated. 

But  to  return  to  the  Greenford  Green  factory.  After  eleven 
years'  successful  working  with  mauve  and  certain  of  its  deriva- 
tives, the  Britannia  violets,  and  a  few  other  dyes  which  are 
given  in  the  subjoined  list,  a  new  impetus  suddenly  came 
through  the  announcement  in  1868  that  Messrs  Graebe  and 
Liebermann,  in  Germany,  had  discovered  that  alizarin,  the 
colouring  matter  of  the  madder  plant,  was  a  derivative  of  the 
coal-tar  hydrocarbon]  anthracene,  and  not,  as  had  formerly  been 
supposed,  a  derivative  of  naphthalene.  The  German  chemists 
found  also  that  the  compound  could  be  prepared  from  anthracene, 


246         THE   BRITISH   COAL-TAR   INDUSTRY 

and  thus  was  accomplished  the  first  laboratory  synthesis  of  a 
natural  colouring  matter.  1  may  perhaps  be  allowed  to  quote  the 
following  passage  from  my  Royal  Society  obituary  notice  : — 

"  This  discovery  had  a  great  influence  upon  Perkin's  career 
as  an  industrial  chemist,  and  may  indeed  be  considered  to  have 
marked  a  new  phase  of  his  activity  in  this  field.  There  was  no 
living  worker  in  this  country  at  that  time  besides  Perkin  who 
so  completely  combined  in  himself  all  the  necessary  qualifications 
for  taking  advantage  of  such  a  discovery.  Imbued  with  the 
spirit  of  his  early  ambition  to  produce  natural  compounds  synthe- 
tically, with  more  than  a  decade's  experience  as  a  manufacturer, 
with  the  resources  of  a  factory  at  his  disposal,  and,  not  least, 
with  special  experience  of  anthracene  as  the  very  substance  upon 
which  at  Hermann's  instigation  he  commenced  his  career  in 
research  work,  it  can  readily  be  understood  that  Graebe  and 
Liebermann's  results  should  have  appealed  to  him  with  special 
significance.  The  first  patented  process  of  the  German  discoverers 
was  confessedly  too  costly  to  hold  out  much  hope  of  successful 
competition  with  the  madder  plant,  requiring  as  it  did  the  use 
of  bromine.  Perkin  at  once  realised  the  importance  of  cheapen- 
ing the  process  by  dispensing  with  the  use  of  bromine,  and 
undertook  researches  with  this  object.  As  a  result,  the  following 
year  (1869)  witnessed  the  introduction  of  two  new  methods  for 
the  manufacture  of  artificial  alizarin.  In  one  of  these  processes 
dichloranthracene  was  the  starting-point,  and  in  the  other  the 
sulphonic  acid  of  anthraquinone,  the  first  being  of  special  value 
in  this  country  owing  to  the  difficulty  of  obtaining  at  that  time 
fuming  sulphuric  acid  in  large  quantities.  The  second  process, 
which  is  the  one  still  in  use,  had  quite  independently  been 
worked  out  in  Germany  by  Caro,  Graebe,  and  Liebermann,  and 
patented  in  England  practically  simultaneously  by  these  chemists 
and  by  Perkin."1 

The  demand  for  another  coal-tar  hydrocarbon,  anthracene, 
in  large  quantities  and  in  a  state  of  purity,  necessitated  further 
pioneering  work.  Supplies  of  the  crude  material  had  to  be 
procured,  the  tar  distillers  had  to  be  educated  in  the  production 
of  raw  anthracene,  and  factory  methods  of  purification  had  to  be 
devised.  It  is  unnecessary  for  me  to  remind  you  that  all  these 
requirements  were  met  by  the  science  and  skill  of  Perkin,  then 

1  The  patents  are: — Caro,  Graebe,  and  Liebermann,  No.  1936,  of  25th 
June  1869,  and  W.  H.  Perkin,  No.  1948,  of  26th  June  1869. 


THE   FOUNDING   OF  THE   INDUSTRY        247 

a  young  man  just  turned  thirty  years  of  age.  The  subsequent 
development  of  the  artificial  alizarin  industry  is  too  well  known 
to  need  recital  on  this  occasion.  But  there  is  one  point  in  con- 
nection with  Perkin's  work  in  this  field  which  must  not  be 
forgotten,  and  that  is  the  great  importance  of  the  dichloranthra- 
cene  process  in  this  country  at  the  outset  of  the  new  branch  of 
the  coal-tar  colour  industry.  Perkin,  in  conversation  with  me, 
has  frequently  emphasised  this  point,  and  I  think  it  desirable  on 
the  present  occasion  to  place  once  again  upon  record  this  chapter 
in  the  early  history  of  the  alizarin  manufacture. 

The  two  processes  discovered  by  Perkin,  and  referred  to  in 
the  preceding  extract,  were  the  anthraquinone  process  and  the 
dichloranthracene  process.  In  the  first  of  these  the  anthracene 
is  oxidised  to  anthraquinone,  the  latter  sulphonated  by  heating 
with  strong  sulphuric  acid  to  a  high  temperature,  and  the  sodium 
sulphonate  converted  into  alizarin  by  alkaline  fusion.  The 
sulphonation  by  this  process  yields  a  mixture  of  mono-  and 
di-sulphonic  acids,  and  the  final  product  is  therefore  a  mixture 
consisting  of  alizarin,  anthrapurpurin,  and  some  flavopurpurin. 
This  was  the  process  first  tried  on  the  large  scale  by  Perkin,  as 
well  as  by  the  German  manufacturers.  The  second  process, 
which  was  patented  here  by  Perkin  a  few  months  after  the 
patenting  of  the  anthraquinone  process,  viz.  in  November  1869, 
sets  out  from  dichloranthracene,  which  is  sulphonated  by  ordinary 
strong  sulphuric  acid  and  the  product  submitted  to  alkaline  fusion 
as  before.  Now  dichloranthracene  sulphonates  more  readily  than 
anthraquinone,  and  as  the  product  consists  chiefly  of  a  disulphonic 
acid  of  anthraquinone,  the  "  artificial  alizarin  "  obtained  by  this 
process  consists  mainly  of  anthrapurpurin,  with  some  alizarin  and 
flavopurpurin.  Alizarin,  as  you  are  aware,  gives  bluer  shades  of 
colour  than  anthrapurpurin,  so  that  although  for  certain  purposes 
where  bright  red  was  required  the  mixture  obtained  by  Perkin's 
second  process  possessed  an  advantage,  for  the  production  of  the 
bluer  reds  the  anthraquinone  product  had  the  advantage.  Perkin 
met  this  difficulty  to  some  extent  by  devising  a  method  for 
separating  his  "  alizarin  "  into  "  blue  shade  "  and  "  scarlet  shade," 
but  this  method  was  not  easy  to  carry  out  on  the  large  scale, 
and  added  to  the  cost  of  the  final  products. 

For  the  first  few  years  the  Badische  Company,  which  had 
acquired  the  Caro-Graebe-Liebermann  patent,  worked  by  mutual 
arrangement  in  combination  with  the  Greenford  Green  factory  ? 


248         THE   BRITISH   COAL-TAR   INDUSTRY 

the  latter  having  the  monopoly  of  the  English  markets  1     The 
Germans  were  using  the  anthraquinone  process  almost  exclusively 
this    being,  as  you  are  aware,  the  method  still  in  use.     When 
ordinary  English  oil  of  vitriol  is  used  for  sulphonating,  a  great 
excess  of  acid  is  necessary  and  there  is  much  loss  owing  to  the 
high  temperature,  so  that  the  dichloranthracene  process  from  this 
point  of  view  had  the  advantage.     Moreover,  when  anthrapur- 
purm  was  the  mam  object  of  manufacture  it  was  found  that  the 
product   obtained  by  the   dichloranthracene  process  gave  much 
purer  shades  than  that  obtained  by  the  anthraquinone  process." 
It  would  have  naturally  occurred  to  Perkin  in  working  out  this 
last  process  to  try  fuming  sulphuric  acid  as  a  sulphonating  agent, 
and  he  did  so  with  success;  but  this  method,  although  giving 
better  results  in  the  way  of  yield  and  uniformity  of  product,  was 
placed   at   a   disadvantage   here   on   account  of  the  cost  of  the 
turning  acid.     The  advantages  arising  from  this  method  of  sul- 
phonating are,  I  may  remind  you,  an  increased  yield  on  account 
of  the  lower  temperature  at  which  the  acid  does  its  work,  and  a 
product   which   consists    mainly   of   the   monosulpho   acid    and 
which  therefore  gives  chiefly  the  true  "alizarin"   on  alkaline 
fusion.     Now  Germany  was,  at  that  time,  the  only  country  in 
which  the  manufacture  of  fuming  sulphuric  acid  was  carried  on 
and  this  gave  them  a  distinct  advantage  in  working  the  anthra- 
quinone process.     Perkin  has  called  attention  more  than  once  to 
the /ta'e  ,ot  aia!rsj  m  thjs  country  during  the  early  life  of  the 
artificial  alizarin  industry,  and  I  cannot  do  better  than  quote  his 
own  statements  : — 

"On  account  of  the  expense  and  difficulty  in  getting  Nord- 
hausen  sulphuric  acid  imported  into  this  country-few  vessels 
liking  it  as  a  cargo— we  commenced  working  with  ordinary 
sulphuric  acid.  We  usually  employed  four  or  five  parts  of  this 


f>r 

'  ahzarm,"  consistmg  chiefly  of  anthrapurpurin.  It  may  be  pofnted  out  also 
that,  owing  to  some  peculiarity  m  the  internal  administration  of  the  German 
Patent  Laws  at  that  time,  the  rights  of  Caro,  Graebe,  and  Liebermann  could 
not  be  secured  m  certain  States,  and  so  other  manufacturers  took  up  "he 
TnfmdUSTryuanduentered  into  competition  with  the  BadLche 

t0  '-n,  the  anthraouinone  process 


THE   FOUNDING   OF  THE   INDUSTRY        249 

to  each  part  of  anthraquinone  and  heated  the  mixture  to 
27O°-28o°  C.  .  .  .  I  find  we  employed  this  process  principally 
in  our  works  until  the  middle  of  June  1870.  We  then  began 
to  work  on  a  larger  scale  than  we  had  hitherto  done  with  di- 
chloranthracene,  and  carried  both  processes  on  for  a  time,  but 
finding  the  latter  the  more  economical,  partially  on  account  of 
the  ease  with  which  it  yielded  the  sulpho  acids  with  ordinary 
sulphuric  acid,  we  employed  it  almost  exclusively  after  a  time, 
although  frequently  making  colouring  matter  by  the  other 
method. 

"  The  large  quantity  of  ordinary  sulphuric  acid  which  had  to 
be  employed  to  convert  anthraquinone  into  the  sulpho  acids,  and 
the  high  temperature  which  had  to  be  used,  causing  a  certain 
amount  of  destruction  to  take  place,  evidently  showed  that  it 
was  desirable  to  employ  fuming  sulphuric  acid  in  this  process. 
In  this  country  we  found  it  costly,  but  as  it  was  more  readily 
procurable  in  Germany,  the  manufacturers  there  used  it.  They 
were  afterwards  supplied  with  a  very  strong  fuming  acid  from 
Bohemia,  containing  about  40  per  cent,  of  sulphuric  anhydride  " 
("The  History  of  Alizarin,"  /.  Soc.  Arts.)  1879,  PP-  24~25)-1 

The  same  statement  was  repeated  in  substantially  identical 
terms  in  1896.  Referring  to  the  loss  of  anthraquinone  when 
ordinary  sulphuric  acid  is  used,  he  says  :- — "  The  means  of  over- 
coming this  difficulty  was  to  use  fuming  sulphuric  acid,  with 
which  anthraquinone  combined  at  a  much  lower  temperature,  but 
the  only  acid  of  the  kind  then  made  was  the  old-fashioned  Nord- 
hausen  acid.  We  imported  a  quantity  of  this,  and,  of  course, 
found  it  to  work  satisfactorily,  but  the  difficulties  and  expense 
connected  with  the  carriage  and  transport  of  this  substance  on 
account  of  its  dangerous  nature — supplied  as  it  then  was  in  large 
earthenware  bottles — made  it  unsuitable  for  use  in  this  country. 

"The  artificial  alizarin  we  first  made  was  produced  by  the 
anthraquinone  process,  the  method  still  used  for  its  manufacture, 
but  the  difficulty  in  preparing  the  sulphonic  acid  in  those  early 
days  just  referred  to  caused  us  to  turn  our  attention  to  the  second 
process  I  had  discovered,  in  which  dichloranthracene  was  used.  .  .  . 

1  The  use  of  Nordhausen  acid  for  the  anthraquinone  process  in  Germany 
began  about  1871;  the  introduction  of  the  stronger  acid  referred  to  by 
Perkin  in  the  above  passage  is  generally  attributed  to  Koch  in  1873.  Dr 
Caro  informs  me  that  he  has  been  unable  to  find  the  authority  for  this 
statement. 


250         THE   BRITISH    COAL-TAR   INDUSTRY 

Without  this  process  the  manufacture  of  artificial  alizarin  in  this 
country  could  not  have  been  carried  on  with  much  success  in  the 
early  days  of  its  manufacture "  (Hofmann  Memorial  Lecture, 
see  p.  1 8 1,  ante). 

The  "  contact,"  or  "  catalytic,"  process  for  producing  sulphuric 
anhydride  introduced  about  the  same  time  in  this  country  by 
Messrs  Chapman,  Messel  &  Co.,  and  in  Germany  by  the  late 
C.  Winkler,  dates  from  1875,  so  tnat  Perkin's  share  in  the 
founding  of  this  great  industry  does  not  consist  only  in  his 
having  given  us  the  practical  methods  for  realising  Graebe  and 
Liebermann's  synthesis  in  the  factory,  but  in  having  devised  a 
process  which,  so  to  speak,  enabled  the  new  industry  to  be  nursed 
through  its  infancy  in  this  country  and  without  which  it  would 
probably  not  have  survived  that  Continental  competition  which, 
as  Perkin  has  told  us,  first  began  to  make  itself  seriously  felt 
about  the  end  of  I873.1  By  that  time  it  was  fully  realised  that 
a  complete  revision  of  the  plant  at  Greenford  Green  had  become 
necessary.  It  required  enlarging  and  modifying  in  order  to  meet 
the  successful  competition  arising  from  the  development  of  the 
anthraquinone  process  in  Germany,  and  a  considerable  expenditure 
of  capital  would  have  been  necessary  to  carry  out  this  work.  But 
Perkin,  whose  ambition  it  had  always  been  to  be  able  to  devote 
himself  to  pure  science,  and  whose  personal  requirements  were 
extremely  modest,  found  that  his  manufacturing  career  had  by 
then  provided  him  with  sufficient  means  to  enable  him  to  retire, 
and,  rather  than  incur  the  responsibility  of  making  a  fresh  start, 
he  took  advantage  of  the  opportunity  for  withdrawing  altogether 
from  the  industry.  His  career  as  a  manufacturer  terminated  in 
1874,  the  Greenford  Green  works  having  then  been  purchased 
by  Messrs  Brooke,  Simpson  &  Spiller,  which  firm,  soon  after- 
wards, transferred  them  to  Messrs  Burt,  Bolton  &  Haywood, 
who  shifted  the  manufacture  from  Greenford  Green  to  Silvertown, 
and  ultimately  from  this  firm  the  "  British  Alizarin  Company " 
was  developed  and  is  still  at  work.  Perkin  always  wished  it  to 
be  known  that  he  considered  the  Silvertown  works  as  the  lineal 
descendant  of  the  first  coal-tar  colour  factory. 

In  this  sketch  of  the  founding  of  the  coal-tar  colour  industry 

I  have  necessarily  limited  myself  to  the  history  of  the  Greenford 

Green  factory.    These  works  would  now  appear  quite  insignificant 

in    comparison    with    any  of   the  great  German  establishments. 

1  "History  of  Alizarin,  "y.  Soc.  Arts,  1879  (see  p.  57,  ante}. 


THE   FOUNDING   OF  THE   INDUSTRY        251 

Although  for  the  most  part  fallen  into  disuse,  they  were  visited 
with  feelings  of  veneration  by  a  large  party  of  our  foreign  guests 
during  the  Jubilee  Meeting  in  1906.  Their  erection  in  1857 
and  their  subsequent  history  had  marked  an  epoch  in  the  annals 
of  applied  science,  the  importance  of  which  was  known  full  well 
to  those  who  had  come  to  this  country  to  render  homage  to  their 
founder.  The  whole  output  of  dyes  from  these  works  during 
the  seventeen  years  that  Perkin  was  connected  with  them  was  not 
very  great  as  measured  by  modern  standards.  Nevertheless,  it 
may  fairly  be  said  that  no  single  factory  established  in  this  country 
has  ever  given  rise  to  such  world-wide  developments,  both  scientific 
and  industrial.  When  it  fell  to  my  lot  to  take  part  in  the  organi- 
sation of  the  jubilee  celebration  in  1906,  it  occurred  to  me  that 
it  would  be  of  interest  to  place  upon  record  the  complete  history 
of  the  Greenford  Green  factory  as  a  colour-making  establish- 
ment, and  Sir  William  Perkin  was  good  enough  to  prepare 
for  me  the  following  list,  which  has  not  yet  seen  the  light  of 
publication  : — 

THE  PRODUCTS  MANUFACTURED  AT  GREENFORD  GREEN, 

1857-1873 

Mauve. — Large  quantities  manufactured. 

Dahlia.— Ethylmauveine,  C27H23(C2H5)N4 .  HC1.  Made 
about  the  same  time  as  Hofmann's  violet  [1863].  The  colour 
was  much  admired,  but  being  very  expensive  was  not  largely 
used.  (Jour.  Chem.  Soc.,  1879,  v°l-  xxxv.  p.  399-) 

Aniline  Pink. — First  found  in  washings  from  mauve,  after- 
wards produced  by  oxidising  mauve  with  lead  peroxide.  It  is 
parasafranine.  Made  about  the  same  time  as  dahlia.  (Jour.  Chem. 
Soc.)  1879,  v°l*  xxxv.  p.  407.)  The  researches  were  made  many 
years  before  publication. 

Magenta. — Prepared  by  mercuric  nitrate  under  a  patent  in  my 
name  ;  a  communication  from  abroad.  It  was  first  obtained  in 
crystals  in  this  way.  (Jour.  Chem.  Soc.^  1862,  vol.  xv.  pp.  238- 
240.)  The  research  was  made  some  years  before  publication. 
The  process  was  dangerous  and  not  carried  on  very  long. 

Amidoazonaphthalene. — Used  in  a  finely  precipitated  form  as 
an  orange,  red,  or  scarlet  pigment  for  calico  printing,  but  not 
largely. 

Britannia  Violet  (various  shades). — Made  from  magenta,  the 
bromine  compound  of  turpentine,  and  methylated  spirit,  or, 


252         THE   BRITISH   COAL-TAR   INDUSTRY 

better,  purified  wood  spirit.  At  first  thought  to  be  a  turpentine 
derivative,  but  afterwards  found  to  be  methylated  rosanilines. 
Made  in  large  quantities. 

Perkins  Green. — This  was  an  interesting  compound  made  by 
treating  Britannia  violet  (blue  shade)  with  acetyl  chloride.  The 
latter  was  made  in  large  quantities  from  phosphorus  trichloride 
and  acetic  acid.  The  phosphorus  trichloride  was  made  in  cast- 
iron  retorts  with  iron  condensers  from  phosphorus  and  dry  chlorine. 
The  colouring  matter  was  obtained  in  a  crystalline  condition,  but 
was  not  investigated  as  to  its  constitution.  It  was  rather  ex- 
tensively used  for  calico  printing  when  iodine  green  was  too 
expensive. 

"  Alizarin" — Produced  very  largely,  chiefly  by  dichloranthra- 
cene  process.  It  consisted  of  anthrapurpurin  and  alizarin,  chiefly 
of  the  former.  These  were  also  separated  and  sold  as  "  scarlet 
shade  alizarin  "  and  "  blue  shade,"  but  we  chiefly  sold  the  mixture 
known  as  "  red  shade." 

Besides  the  above  we  made  suitable  mixtures  of  aniline  salts, 
oxidising  agents,  and  copper  compounds  for  the  production  of 
aniline  black.  Also  the  colouring  matters  were  made  into "  lakes  " 
by  processes  of  our  own  for  paperhangings  and  lithographic  and 
other  printing  inks  in  considerable  quantities. 

This  list  contains  what  may  be  regarded  as  Perkin's  direct 
contribution  to  the  colour  industry  as  a  manufacturer.  It  may 
not  appear  very  imposing  to  us  now,  but  we  must  read  into  it 
all  that  it  means  in  order  to  appreciate  its  full  significance.  Con- 
sider the  pioneering  work  in  every  direction  that  had  to  be  done 
in  order  to  accomplish  these  results.  Consider  further  that  they 
were  achieved  at  the  outset  by  a  youth  of  about  eighteen,  and 
brought  to  a  successful  termination  in  seventeen  years  by  a  young 
man  thirty-six  years  of  age,  and  that  during  the  whole  of  that 
period,  while  the  factory  was  actively  at  work,  a  continuous  stream 
of  scientific  research  was  kept  going  in  his  laboratory.  Consider 
also  the  stupendous  consequences  of  the  initiation  of  this  industry, 
and  then  you  will  realise  the  extent  of  our  indebtedness  to  the 
man  whose  labours  in  this  field  I  have  attempted  to  give  you  an 
account  of.  I  am  aware  that  by  many  who  regard  manufacturing 
industry  from  a  narrowly  patriotic  point  of  view  Perkin  has  been 
censured  for  withdrawing  so  soon  from  the  scene  of  his  industrial 
operations.  The  reply  to  this  charge  is  obvious.  He  had  made 


THE   FOUNDING   OF   THE   INDUSTRY        253 

a  sufficient  fortune  for  his  modest  requirements,  and  the  seeds 
which  he  had  sown  were  developing  rapidly  in  this  country.  At 
that  time  (1874)  German  competition  was  only  just  beginning  to 
make  itself  felt.  The  industry  was  flourishing  here,  and  with 
respect  to  France  it  may  be  said  that  within  a  very  short  period 
of  the  founding  of  the  Greenford  Green  factory,  and  especially 
from  the  time  of  the  discovery  of  magenta,  the  industry  was  also 
in  a  prosperous  condition  there.  How  thoroughly  this  branch  of 
manufacture  had  its  head  centre  in  England  during  the  few  years 
following  the  opening  of  the  Greenford  works  may  be  inferred 
from  the  fact  that  such  men  as  Maule  and  (especially)  E.  C. 
Nicholson,  both  pupils  of  Hofmann,  had  entered  the  industry  ; 
that  in  Manchester  the  firm  of  Roberts,  Dale  &  Co.  had  secured 
the  services  of  men  like  Caro  and  Martius,  who  later  became 
pioneers  in  the  German  colour-making  industry.  Or,  if  we  turn 
to  the  actual  products,  we  find  that,  in  addition  to  those  emanat- 
ing from  the  firm  of  Perkin  &  Sons,  Simpson,  Maule  &  Nichol- 
son had  secured  the  first  really  valuable  process  for  making 
magenta,  viz.  the  arsenic  acid  process  of  Medlock  ;  that  they 
had  also  secured  the  beautiful  process  of  Girard  and  De  Laire 
for  phenylating  magenta  so  as  to  convert  it  into  blue  and  violet 
colouring  matters,  and  that  Nicholson,  by  his  discovery  of  the 
method  of  sulphonation,  had  developed  these  into  what  were 
for  many  years  the  most  important  of  all  the  coal-tar  colouring 
matters.  This  firm  had  also  introduced  aniline  yellow  (aminoazo- 
benzene),  the  precursor  of  the  basic  azo  dyes,  and  phosphine 
(chrysaniline),1  the  first  member  of  the  acrid  ine  series.  They 
were,  moreover,  the  only  manufacturers  of  the  alkylated  rosani- 
lines  under  Hofmann's  patent.  Then  the  firm  of  Roberts,  Dale 
&  Co.  were  making  picric  acid,  and  had,  through  Caro,  given  to 
the  industry  the  first  induline  obtained  from  aniline  yellow  and 
aniline,  as  well  as  Manchester  brown  or  Bismarck  brown.  This 
firm  had  also,  through  Martius,  given  us  the  dinitronaphthol 
known  as  Manchester  yellow.  Cyanine,  or  quinoline  blue,  the 
first  representative  of  a  group  of  colouring  matters  which  have 
since  become  of  great  importance  as  special  sensitisers  for  photo- 

1  In  the  1866  catalogue  of  this  firm,  already  referred  to,  aniline  yellow  is 
priced  at  25.,  and  phosphine  at  35.  per  oz.  The  Nicholson  blues  were,  at 
that  time,  sold  only  in  solution,  the  price  ranging,  according  to  the  brand, 
from  155.  to  305.  per  gallon.  Solid  "Regina  purple"  is  priced  at  155. 
per  oz. 


254         THE   BRITISH   COAL-TAR   INDUSTRY 

graphic  purposes,  was  discovered  the  same  year  as  mauve  (1856) 
by  Greville  Williams,  who  was  for  some  time  chemist  at  the 
Perkins'  factory,  and  who  afterwards,  with  Messrs  E.  Thomas 
and  J.  Dower,  started  the  Star  Chemical  Works  at  Brentford. 
This  country  may  also  claim  to  have  been  the  pioneer,  through 
Crace-Calvert  and  Lowe,  of  Manchester,  in  the  technical  pro- 
duction of  highly  purified  phenol.1  The  first  successful  method 
for  printing  on  the  fabric  with  aniline  black  was  discovered  and 
patented  in  1863  by  John  Lightfoot,  of  Accrington. 

This  was  the  state  of  affairs  during  Perkin's  connection  with 
the  industry,  and,  superadded  to  this  manufacturing  activity,  was 
the  supremely  important  fact  that,  until  1865,  the  great  master, 
Hofmann,  was  among  us,  and  that  the  laboratory  at  the  Royal 
College  of  Chemistry  had  become  a  centre  of  active  research  in 
the  chemistry  of  colouring  matters  which  stimulated  the  industry 
and  supplied  chemists  for  the  factories.2  Nor  must  it  be  for- 
gotten that  Peter  Griess,  the  founder  of  diazo  chemistry,  was 
working  over  here  during  the  greater  part  of  the  same  period. 
It  cannot  be  said  that  Perkin  abandoned  the  ship  in  a  sinking 
condition  ;  on  the  contrary,  she  was  steaming  full  speed  ahead  ! 
For  any  scuttling  that  may  have  afterwards  occurred  he  can  in  no 
way  be  held  responsible. 

The  indebtedness  of  the  colour-making  industry  to  the 
founder  of  the  first  coal-tar  colour  factory  does  not,  however, 
begin  and  end  with  his  career  as  a  manufacturer.  The  example 
which  he  has  set  us  as  a  man  will  for  all  time  serve  to  point  the 
moral  that  all  those  qualities  which  make  for  success  in  industrial 
pursuits — scientific  ability  and  knowledge,  inexhaustible  patience, 
perseverance,  resourcefulness,  and  energy — may  be  conjoined 
with  the  highest  and  best  attributes  of  humanity.  Such  was  the 
personality  of  the  man  whose  labours  have  added  lustre  to  the 
scientific  and  industrial  history  of  our  country,  and  whose  loss 
touches  us  the  more  deeply  as  representatives  of  that  special 

1  The  state   of  the  industry   here   and   in   France   five   years   after  its 
inauguration    at    Greenford   Green    can    be  ascertained    from    Hofmann's 
report  on  the  chemical  exhibits  at  the  International  (London)  Exhibition 
of  1862.     It  is  not  going  too  far  to  say  that  during  its  early   years   the 
coal-tar  colour  industry  was  essentially  English  and  French. 

2  Hofmann  left  London  in  1865.     From  that  time  until  the  creation  of 
the  Chair  of  Organic  Chemistry  at  Owens  College,  Manchester,  in  1874,  to 
which   Schorlemmer  was    appointed,   there   was   no   professorship    in    this 
department  of  the  science  in  this  country. 


THE   FOUNDING   OF  THE   INDUSTRY        255 

industry  which,  in   its   present    form,  embodies    the    developed 
results  of  his  pioneering  efforts. 

ADDENDUM 

As  the  introduction  of  fuming  sulphuric  acid  played  such  an 
important  part  in  the  early  history  of  the  artificial  alizarin  in- 
dustry, I  have  thought  it  of  interest  to  append  the  following 
account  kindly  furnished  by  Hofrath  Dr  Caro.  It  may  be 
pointed  out  that  the  "  contact "  process  for  producing  sulphuric 
acid  dates  from  I875,1  and  therefore  subsequently  to  Perkin's 
retirement,  so  that  it  was  his  successors  who  had  the  advantage 
of  this  new  branch  of  manufacture  : — 

"Previously  to  the  publication  of  Clemens  Winkler,  the 
entire  c  Nordhausen  Fuming  Sulphuric  Acid  '  was  manufactured 
by  John  David  Starck  in  Bohemia  (in  several  works  near  Pilsen), 
and  was  largely  imported  into  England.  It  originally  contained 
about  20  per  cent,  of  the  free  anhydride.  This  acid  was 
employed  by  Perkin  in  his  first  experimental  manufacture  in 
1869  for  sulphonating  anthraquinone,  and  was  afterwards  in  1870 
exchanged  for  ordinary  sulphuric  acid,2  while  we  (the  Badische 
Company)  commenced  at  this  same  period  with  the  ordinary  acid 
and  gradually  went  on  increasing  its  strength  by  adding  fuming  acid 
containing  about  24  per  cent,  of  free  anhydride.  I  recollect  that 
in  1873  we  used  chiefly  a  mixture  of  two  parts  of  the  said  fuming 
acid  with  one  part  of  the  monohydrate.  At  the  same  time 
we  studied  carefully  the  effect  of  the  increased  strength  of  the 
sulphonating  agent  upon  the  separate  production  of  the  mono- 
and  disulpho-acids  of  anthraquinone,  and  I  believe  that  at  the 
same  time  (1873)  similar  experiments  were  made  by  all  German 
alizarin  makers,  particularly  by  Gebrilder  Gessert  &  Co. 
at  Elberfeld,  and  that  in  consequence  of  the  superior  results 
obtained  by  the  action  of  stronger  acid  at  a  correspondingly  lower 
temperature  a  demand  was  created  for  fuming  sulphuric  acid  of 
greater  strengths  than  hitherto  supplied.  Thus  John  David 

1  The  patent   of  Messrs  Chapman  &  Messel  is  dated  i8th  September 
1875.     Winkler's  process  was  described  in  Dingier 's  Polytechnisches  Journal 
for  October   1875.     Dr  Messel  gave  a  description  of  their  process  before 
the  Chemical  Society  in  April  1876,  but  the  paper  was  not  published  by  the 
Society. 

2  See  Perkin's  statement  (ante)  quoted  from  his  "  History  of  Alizarin," 
1879. 


256         THE   BRITISH    COAL-TAR   INDUSTRY 

Starck  was  led  to  manufacture  the  solid  fuming  sulphuric  acid 
containing  about  45  per  cent,  of  the  free  anhydride.  This  was, 
I  think,  in  1873  or  1874.  In  1875  we  employed  regularly  the 
fuming  acid  of  45-50  per  cent,  of  anhydride.  In  1877  we  went 
further  in  increasing  the  energy  of  the  sulphonating  action  by  the 
employment  of  fuming  acid  of  from  68  to  72  per  cent,  of  free 
anhydride,  which  we  prepared  by  distilling  the  anhydride  from 
one  portion  of  fuming  acid  into  another  portion  of  fuming  acid, 
containing  45-50  per  cent,  of  free  anhydride.  We  also  distilled 
the  anhydride  into  the  sulphonating  mixture  of  anthraquinone 
with  fuming  acid.  Immediately  after  the  publication  of  Winkler 
in  1875  we  commenced  experimenting  with  his  synthetical 
process,  and,  after  having  many  times  changed  our  experimental 
plant,  we  succeeded  in  manufacturing  the  fuming  acid  on  a  very 
large  scale  from  1877.  At  about  the  same  time  other  manu- 
facturers started  the  manufacture  of  fuming  acid  by  the 
synthetical  process." 


XIX.:    I9o8 

LETTER  FROM  PROFESSOR  H.  CARO  TO 
PROFESSOR  R.  MELDOLA,  MAY   1908 

THE  following  letter  from  Hofrath  Dr  Heinrich  Caro  of  Mannheim, 
formerly  chemical  director  of  the  Eadische  Anilin-  und  Soda-Fabrik,  is 
inserted  here  on  account  of  its  historical  interest.  It  bears  the  date 
ityh  May  1908,  and  relates  to  Professor  Meldolas  address  to  the 
Society  of  Dyers  and  Colourists  on  "  The  Founding  of  the  Coal-tar 
Colour  Industry"  (ante,  p.  234).  Dr  Caro  had  undertaken  to  write 
an  obituary  notice  of  Sir  William  Perkin  for  the  German  Chemical 
Society,  but  he  died  before  the  completion  of  the  work.  Professor 
Meldolas  obituary  notice  from  the  Chemical  Society's  Journal  (ante, 
p.  233)  was  therefore  translated  and  adopted  after  some  curtailment  by 
the  German  Society  ("  Berichte"  1911,  vol.  xliv.}.  The  letter  is 
given  in  Dr  Caws  own  words  without  modification  : — 

"  MY  DEAR  PROFESSOR  MELDOLA, — Having  now  over  and  over 
again  perused  your  excellent  historical  account  of  c  The  Founding 
of  the  Coal-tar  Colour  Industry,'  which  you  have  so  kindly 
sent  to  me,  I  beg  to  offer  to  you  both  the  expression  of  my 
sincere  thanks  and  of  my  great  admiration.  Although  the  main 
object  of  your  Presidential  Address  to  the  Society  of  Dyers  and 
Colourists  has  been  to  erect  an  everlasting  monument  to  the 
memory  of  Sir  William  Henry  Perkin's  industrial  pioneering  work 
in  the  field  of  the  coal-tar  dyes — thus  supplementing  your  prior 
address  to  the  Royal  Society,1  in  which  you  so  splendidly  depicted 
the  life  and  the  scientific  research  work  of  Perkin, — you  have  given 
to  the  world  more  than  a  mere  personal  and  biographical  account 
of  the  great  chemist  and  manufacturer.  In  those  two  joint  pub- 
lications you  have  embodied  such  a  fulness  of  historical  facts, 

1  Obituary  Notice:   the  Chemical  Society's  notice  comprises  both   the 
scientific  and  technical  sides  of  Perkin's  work. 

257  17 


258         THE   BRITISH   COAL-TAR   INDUSTRY 

partly  as  yet  unknown,  and  commented  upon  by  your  own 
authoritative  remarks,  that  your  Perkin  Essays  will  for  ever  rank 
amongst  the  most  valuable  contributions  to  the  chemical  history 
of  the  last  fifty  years.  You  must  have  devoted  an  enormous 
amount  of  thought,  time,  and  labour  in  order  to  collect  and 
artistically  to  arrange  the  documentary  evidence  upon  which  you 
have  erected  such  a  monumentum  <ere  perennis  worthy  of  Sir 
William  Henry  Perkin  and  his  time. 

"  I  now  feel  justly  afraid  to  proceed  with  my  own  biographical 
work  on  Perkin's  life,  which  work  is  still  in  its  infancy  and  which 
I  have  been  unwise  to  promise  to  the  German  Chemical  Society. 
You  have  already  said  everything  that  could  be  said  on  the 
subject  of  Perkin's  life-work,  and  it  will  be  very  difficult,  if  not 
impossible,  for  me  to  discharge  my  task  without  following  in 
your  wake  and  copying  your  writings.  On  the  other  hand,  I 
ought  to  be  very  thankful  to  you  for  having  paved  my  way. 

"  You  have  kindly  asked  me  whether  I  intend  coming  to  the 
International  Congress  of  Applied  Chemistry  in  London  in  1909. 
1  would  certainly  like  to  do  so,  and  to  visit  once  more  dear  old 
England  and  my  dear  old  English  friends.  If  I  were  only 
ten  years  younger !  But  such  unfortunately  is  not  the  case. 
I  dare  not  forget  that  the  sun  of  my  life  is  setting.  With 
my  kindest  regards, — I  remain,  my  dear  Professor  Meldola, 
yours  faithfully,  DR  H.  CARO." 


XX.:    i9io 

TINCTORIAL    CHEMISTRY,    ANCIENT 
AND    MODERN 

BY  PROFESSOR  R.  MELDOLA,  F.R.S. 

(Presidential  Address,  Society  of  Dyers  and  Colourists  :    Journal  of  the 
Society  of  Dyers  and  Colourists^  1910,  p.  103) 

THE  FIFTEEN-YEAR  PERIOD,   1870—1885,  IN  THE  HISTORY 
OF  THE  COAL-TAR  COLOUR  INDUSTRY,  AND  ITS  LESSONS 

IN  dwelling  upon  the  strengthening  of  the  bonds  between  science 
and  industry  as  one  of  the  most  important  functions  of  this  and 
kindred  societies,  I  am  prompted  by  the  thought  that  the  realisa- 
tion of  the  importance — the  vital  importance — of  this  union  has 
not  been  fully  grasped  in  this  country  even  at  the  present  time. 
Our  industry  in  the  course  of  its  history  has  furnished  abundant 
illustration  of  that  principle  which  we  as  a  nation  have  not 
thoroughly  assimilated — the  direct  practical  bearing  of  science, 
even  in  its  highest  and  most  abstract  form,  upon  technical  and 
manufacturing  operations.  For  more  than  a  quarter  of  a  century 
I  have  taken  every  opportunity  of  emphasising  the  object-lesson 
conveyed  by  the  history  of  that  branch  of  chemical  industry 
which  immediately  concerns  us  here — the  manufacture  of  coal-tar 
products  inaugurated  in  1856  by  my  illustrious  predecessor  in 
this  chair,  whose  services  to  that  industry  formed  the  subject  of 
my  address  two  years  ago.  Perkin  himself  did  more  than  any 
worker  of  his  time  to  inculcate  that  doctrine  both  by  precept  and 
example.  It  is  the  spirit  of  propagandism  which  encourages  me 
to  belabour  this  somewhat  jaded  hobby  on  such  an  occasion  as 
the  present  one,  when  it  is  my  privilege  to  be  able  to  appeal  to 
a  wider  public  through  the  representatives  of  an  art  that  is  well 
to  the  fore  in  the  utilisation  of  the  resources  which  science  has 

259 


260         THE   BRITISH   COAL-TAR   INDUSTRY 

placed  at  its  disposal  and  through  the  members  of  a  Society 
which  may  be  congratulated  on  doing  good  service  to  that  cause 
which  we  all  have  at  heart.  So  far,  however,  as  I  am  concerned, 
the  preaching  of  the  doctrine  that  the  development  of  the  coal- 
tar  colour  industry  is  primarily  the  outcome  of  scientific  research 
is  nothing  more  than  the  iteration  of  ancient  history.  It  is 
interesting  to  note  in  passing  that  it  is  considered  necessary  to 
restate  this  fact  from  time  to  time  with  all  the  air  of  novelty.1 
But  after  all,  if  a  principle  is  true,  and  if  its  truth  is  not  generally 
recognised,  it  may  be  desirable  to  freshen  up  the  public  mind 
from  time  to  time,  if  only  for  the  purpose  of  reinforcing  a  lesson 
which  is  in  danger  of  being  forgotten.  From  the  opinion  recently 
credited  to  some  Hungarian  chemist  (said  to  have  been  twenty 
years  in  an  English  dye-house),  in  the  organ  of  the  Hungarian 
Association  of  Chemical  Industry,2  in  which  both  the  facts  and 
their  conclusions  are  distorted  in  a  most  remarkable  way,  it  is 
perfectly  clear  that  there  is  still  scope  for  reiteration.  Fortun- 
ately, it  is  possible  for  me  to  support  the  position  which  I  have 
always  maintained  by  an  appeal  to  that  particularly  critical  period 
in  the  history  of  the  industry  when  I  was  connected  with  it,  viz. 
the  period  following  the  Franco-Prussian  War  of  1870.  It  was 
soon  after  this  great  European  disaster  that  the  Continental 
manufacturers  began  to  get  seriously  to  work,  and  some  ten 
years  later  we  in  this  country  and  the  French  manufacturers  ex- 
perienced the  first  symptoms  of  serious  competition  from  the 
introduction  of  new  products  resulting  from  German  discoveries. 
Before  1870  and  for  a  few  years  subsequently  the  list  of  synthetic 
dyestuffs  was  a  short  one.  Those  made  at  Greenford  Green 
during  Perkin's  time  (1857-1873)  were  given  in  a  list  published 
in  my  last  address  to  this  Society  (see  p.  251,  ante).  The  staple 
products  when  I  first  entered  the  industry  in  1870  were  magenta 
and  the  blues  derived  therefrom,  the  Hofmann  violets,  the 
Britannia  violets  of  Perkin,  Bismarck  brown,  Manchester  yellow, 
indulines,  alizarin,  and  methyl  violet,  the  latter  discovered  by 
Lauth  in  1861  and  manufactured  in  Poirrier's  factory  near  Paris. 
A  few  minor  products,  such  as  phosphine,  aniline  yellow,  aldehyde 
green,  etc.,  were  made  by  certain  firms,  but  it  is  unnecessary  to 
swell  the  list.  No  good  green  for  dyeing  purposes  was  known, 
and  the  so-called  "  iodine  green  "  was  too  costly  and  fugitive  to 

1  See  The  Times'  "Engineering  Supplement,"  i;th  November  1909. 

2  Ibid.)  gth  February  1910. 


TINCTORIAL   CHEMISTRY,    1870-1885          261 

be  of  much  use.  At  the  time  of  my  second  connection  with  the 
coal-tar  colour  industry,  which  began  in  1877,  the  °ld  state  of 
affairs  was  beginning  to  change — at  first  slowly,  but  with  increas- 
ing velocity — and  at  the  time  of  my  severance  in  1885  the 
change  was  progressing  with  such  speed  that  I  foresaw  the 
approaching  decline  of  our  supremacy  in  that  industry,  and  did 
my  best  on  every  possible  occasion  to  direct  public  attention  to 
the  existing  state  of  affairs. 

Now  it  happens  that  the  period  covered  by  my  own  personal 
reminiscences — say  from  187010  1885 — was  the  most  active  in 
the  discovery  of  new  types  of  colouring  matters  in  the  whole 
history  of  the  industry.  I  do  not  mean  to  say  that  no  new  types 
have  been  discovered  since  1885,  or  that  the  actual  numbers  of 
individual  dyes  put  on  the  market  since  that  date  may  not  have 
been  greater  than  before  that  date.  But  it  is  the  discovery  of 
new  types  or  of  the  chemical  constitution  of  old  types  which  is 
the  scientific  achievement  which  precedes  and  prompts  the 
industrial  development  and  furnishes  the  manufacturer  with  the 
means  of  producing  new  compounds  of  tinctorial  value.  With 
the  unravelling  of  chemical  structure  comes  suggestions  for  new 
methods  of  producing  compounds  of  certain  specific  types,  so  that 
the  clue  furnished  by  the  determination  of  the  constitution  of 
one  compound  may  lead  to  innumerable  compounds  of  the  same 
type  being  made  available  for  tinctorial  industry.  It  may  be 
instructive  to  recall  a  few  of  the  more  conspicuous  cases  which 
occurred  during  the  period  under  consideration.  By  way  of 
preliminary  introduction  it  may  be  well  to  remind  you  of  the 
fact  that  the  leading  idea  which  furnished  the  key  to  the  constitu- 
tional formulae  of  the  organic  compounds  being  dealt  with  in  the 
colour  industry,  was  the  application  of  what  is  now  called  the 
doctrine  of  valency  to  carbon  compounds,  and  especially  to 
benzene  and  its  derivatives,  by  Kekule"  in  1865.  That  epoch- 
making  idea  made  its  way  very  slowly  in  this  country,  while  in 
Germany  it  was  being  rapidly  assimilated.  I  well  remember  in 
the  early  years  of  my  connection  with  the  Chemical  Society,  that 
the  importance  of  the  new  benzene  theory  was  realised  by  only 
a  very  small  number  of  our  scientific  chemists  ;  by  the  technical 
chemists  and  manufacturers  it  was  openly  scoffed  at,  and  those 
who  made  use  of  the  new  ideas  in  their  writings  were  jeered  at 
for  "  knocking  about  benzene  rings."  But  if  our  manufacturers 
failed  to  see  any  connection  between  an  abstract  theoretical  con- 


262         THE   BRITISH    COAL-TAR   INDUSTRY 

ception  and  its  practical  applications,  this  was  not  the  case  else- 
where, and  the  examples  which  I  propose  to  give  will  show  some 
of  the  results. 

The  oldest  and  most  largely  made  dyestuff  in  the  early  days 
of  the  industry  was  magenta  or  fuchsine,  for  the  full  history  of 
which  I  refer  you  to  the  books.  This  colouring  matter  had 
been  made  the  subject  of  much  scientific  study  by  many  dis- 
tinguished chemists,  and  its  chemical  composition  and  mode  of 
formation  were  well  known.  But  its  chemical  constitution  was 
a  mystery  till  the  year  1878,  when  the  problem  was  attacked  by 
chemists  armed  with  a  new  mental  weapon  and,  therefore,  capable 
of  looking  at  the  question  from  a  new  point  of  view.  That 
weapon  was,  of  course,  the  Kekule  theory,  which  had  by  that 
time  become  part  of  the  mental  equipment  of  every  truly  scientific 
chemist,  and  the  chemists  who  paved  the  way  for  the  solution  of 
this  problem  were  Caro  and  Graebe,  and  the  men  who  finally 
solved  it  were  Emil  and  Otto  Fischer.  It  is  only  necessary  to 
state  the  bare  facts  here  ;  they  are  all  recorded  in  history,  but  I 
shall  never  forget  the  keen  delight  with  which  I  first  read  those 
memorable  papers  of  1878—1880,  in  which  the  Fischers  proved 
that  parafuchsine  and  magenta  were  derivatives  of  the  hydro- 
carbon triphenylmethane  and  its  homologue  respectively.  This 
discovery  settled  a  point  which  had  engaged  the  attention  of 
chemists,  from  Hofmann  downwards,  for  a  period  of  about  twenty 
years.  Turn  now  to  the  practical  consequences  of  this  purely 
academic  piece  of  work.  The  type  had  been  revealed.  Others 
of  the  older  dyestuffs,  such  as  the  methyl  violet  of  Lauth,  the 
Hofmann  violets,  the  phenylated  blues,  etc.,  were  all  seen  to 
belong  to  the  same  type.  Furthermore,  a  well-known  green 
dyestufF,  malachite  green,  discovered  by  O.  Fischer  in  1877  and 
by  Doebner  (independently)  in  1878 — the  first  direct  dyeing 
green  of  real  value — and  a  few  other  greens  introduced  about  the 
same  time  or  a  little  later,  and  all  made  by  the  same  processes, 
were  proved  to  be  derivatives  of  triphenylmethane.  Then 
followed  the  scientific  development  arising  naturally  from  the 
Fischers'  demonstration,  viz.  the  search,  and  the  successful 
search,  for  other  methods  of  building  up  the  triphenylmethane 
type.  Totally  new  methods  were  devised  and  new  branches  of 
the  industry  sprang  into  existence.  In  addition  to  the  aromatic 
aldehyde  method  of  Fischer,  we  had  the  so-called  phosgene 
colours,  such  as  the  Victoria  blues,  night  blue,  crystal  violet, 


TINCTORIAL   CHEMISTRY,    1870-1885          263 

etc.,  all  of  which  appeared  in  1883.  In  rapid  succession  there 
appeared  later  dyes  of  the  same  type  in  which  tetramcthyl- 
diaminobenzhydrol  or  formaldehyde  played  the  part  of  con- 
densing agents.  I  have  taken  the  trouble  of  compiling  some 
lists  (from  Schultz's  tables),  the  results  of  which  bring  out  this 
chapter  of  applied  chemistry  in  a  very  vivid  way.  Before  the 
Fischers'  work,  there  were  on  the  market,  roughly  speaking,  some 
twenty  dyes  of  this  class.  I  refer  only  to  the  basic  dyes  or  their 
suJphonic  acids.  Many  of  these  older  dyes  were  not  definite 
compounds  at  all,  but  indefinite  mixtures  or  residues  and  by- 
products. Now  the  manufacture  of  magenta  began  on  the 
small  scale  in  France  about  1859,  so  that  the  twenty  dyes  (of 
which  only  some  fifteen  can  be  claimed  as  definite  products)  re- 
present a  period  of  activity  of  nineteen  years.  From  1878  to 
1891,  the  latest  date  in  Schultz's  tables  for  a  colouring  mattter  of 
this  type  (Green's  ed.  of  1894),  i.e.  during  a  period  of  thirteen 
years,  twenty-four  new  colouring  matters  of  this  class  were  intro- 
duced, everyone  a  definite  compound  and  some  of  them  competing 
with  and  ultimately  displacing  some  of  the  older  dyes  of  the  same 
class,  which,  up  to  that  period,  had  been  the  staple  products  upon 
which  some  of  our  manufacturers  here  had  absolutely  depended 
to  keep  their  works  going. 

1  now  turn  to  another  large  and  important  group  of  colouring 
matters,  the  discovery  of  which  belongs  to  the  period  with  which 
I  am  dealing.  In  1871,  Professor  v.  Baeyer  published  the  first 
of  a  series  of  papers  on  some  new  types  of  compounds  which 
he  had  obtained  by  the  condensation  of  phenols  with  phthalic 
anhydride  and  which  he  termed  "  phthalems."  This,  as  in  the 
previous  case,  was  at  first  a  piece  of  purely  scientific  work. 
Now,  fortunately  for  that  country,  Germany  had  in  one  of  her 
new  colour  factories  a  chemist  whose  services  we  in  this  country 
had  lost — a  man  whose  name  will  be  indelibly  stamped  upon  the 
history  of  the  development  of  the  coal-tar  colour  industry.  I 
refer  to  my  old  friend  Dr  Heinrich  Caro,  of  Mannheim.  It 
was  he  who  recognised  the  technological  importance  of  Baeyer's 
work,  and  turned  this  "  academic  "  chemical  reaction  into  a  manu- 
facturing process  by  his  discovery  that  the  substituted  phthalems 
were  possessed  of  great  tinctorial  value.  Thus  appeared  in  1874 
the  eosins,  the  bromo-derivatives  of  resorcin-phthale'm,  and  I  have 
a  vivid  recollection  of  the  excitement  with  which  I  first  experi- 
mented with  some  of  these  beautiful  new  dyes  when,  somewhat 


264         THE   BRITISH   COAL-TAR   INDUSTRY 

later,  they  first  found  their  way  to  this  country.  The  subsequent 
history  is  substantially  as  before.  The  principle  that  substituted 
phthalems  were  dyestuffs  had  been  discovered  ;  further  discovery 
for  some  years  turned  upon  methods  for  introducing  various  sub- 
stituents  into  the  phthale'lns,  and  the  list  was  rapidly  extended. 
From  this  discovery  of  Baeyer's  in  1871  there  was  thus  developed 
another  branch  of  industry,  creating  a  demand  for  raw  materials 
such  as  phthalic  anhydride  and  resorcinol,  which  had  never  before 
been  made  on  a  large  scale.  In  the  meantime,  Baeyer  and  other 
Continental  chemists  were  slowly  unravelling  the  mystery  of  the 
chemical  constitution  of  the  phthalems,  and  after  some  years  it 
was  shown  that  they  were  closely  related  in  type  to  the  triphenyl- 
methane  group.  It  may  be  of  interest  to  add  that  the  question 
of  the  constitution  of  these  compounds  is  still  under  investigation, 
but  this  is  a  chapter  of  modern  chemistry.  The  direct  descen- 
dants of  these  earlier  substituted  phthale'ins  are  the  well-known 
rhodamines,  first  introduced  in  1887. 

Another  important  group  of  colouring  matters  belonging  to 
the  same  period  owes  its  origin  to  a  discovery  by  Lauth  in  1876, 
viz.  that  certain  diamines  when  oxidised  in  the  presence  of 
sulphuretted  hydrogen  gave  rise  to  the  formation  of  violet 
dyes.  At  first  this  also  was  a  purely  academic  discovery  ;  Lauth's 
violet  never  became  an  important  addition  to  the  list  of  avail- 
able dyestuffs  on  account  of  its  cost.  But  the  same  year  the 
principle  was  extended  by  Caro,  with  the  result  that  methylene 
blue  was  introduced.  Here  again  I  have  a  vivid  recollection 
of  the  sensation  produced  in  this  country  by  the  introduction  of 
a  new  blue  dyestuff.  Up  to  that  period  all  the  known  blues 
were  phenylated  rosanilines.  No  basic  blue  soluble  in  water  had 
ever  been  available  for  tinctorial  industry.  The  basic  phenylated 
rosanilines  had,  on  account  of  their  insolubility,  to  be  used  in 
alcoholic  solution,  and  the  water-soluble  blues  were  salts  of 
sulphonic  acids.  The  chemical  constitution  of  methylene  blue 
was  attacked  as  a  scientific  problem  by  Bernthsen  in  1883,  and 
successfully  elucidated  in  a  masterly  series  of  researches  which 
bore  the  usual  practical  result.  New  and  more  advantageous 
methods  of  making  the  colouring  matter  were  discovered,  and 
the  original  methylene  blue  was  soon  followed  by  a  number  of 
new  dyestuffs  belonging  to  the  same  type. 

This  same  eventful  period  witnessed  the  introduction  of 
other  great  groups  of  colouring  matters.  It  is  unnecessary  to 


TINCTORIAL   CHEMISTRY,    1870-1885         265 

restate  at  length  histories  which  are  already  upon  record.  I  need 
only  mention  naphthol  yellow  or  acid  yellow  (1879),  tne  oxa" 
zines  (1879),  tne  indophenols  (1881),  the  new  series  of  azo 
colours  which  began  with  chryso'fdine  and  naphthol  orange 
(1875-1876),  fast  red,  the  Ponceaux,  Bordeaux,  and  Biebrich 
scarlet  (1878-1879),  blue  black  (1882),  Congo  red,  the  first 
of  the  direct  cotton  dyes  and  the  first  representative  of  that 
enormous  series  of  azo  colours  derived  from  tolidine,  dianisidine, 
etc.  (1884-1885).  Then  we  had  the  new  series  of  quinoline 
dyes  beginning  with  flavaniline  (1881),  and  the  renewed  interest 
in  the  safranines  and  allied  colouring  matters  arising  from  the 
researches  of  Witt  and  Nietzki,  and  the  consequent  introduc- 
tion of  many  new  dyestuffs  belonging  to  this  type  beginning 
with  phenosafranine  (1878),  the  eurodines  (1879),  neutral  violet 
(1880),  etc.  Safranine,  as  you  will  remember,  was  first  recog- 
nised among  the  products  of  oxidation  of  aniline  (crude)  by 
Perkin  in  1861,  and  his  own  mauve,  the  first  of  the  coal-tar 
dyes,  was  in  later  times  (1888)  proved  by  Fischer  and  Hepp  to 
be  a  member  of  this  same  series.  Within  this  same  period  also 
falls  the  discovery  of  the  first  method  of  producing  the  sulphide 
colours,  which  have  since  become  of  such  great  importance 
and  which  began,  in  germ,  with  the  old  cachou  de  laval  of 
Croissant  and  Bretoniere  in  1873.  So  also  there  remain  to  be 
recorded  the  numerous  and  important  developments  in  the  ali- 
zarin group,  beginning  with  alizarin  orange  (1875),  alizarin 
blue  (1878),  alizarin  blue  S  (1882),  etc.,  gallem  and  ccerule'm 
(1878),  the  first  of  the  hydrazine  colours,  tartrazine  (1884)  ;  and 
sun  yellow,  the  first  of  the  stilbene  dyes  (1883).  And  last,  and 
by  no  means  least,  we  have  the  first  indigo  synthesis  by  Baeyer 
in  1880,  and  the  second  (Baeyer  and  Drewson)  two  years  later, 
and  the  settlement  of  the  constitution  of  this  all-important 
colouring  matter  in  1888  by  this  same  master  worker. 

CHEMICAL  RESEARCH  THE  PRIME  FACTOR  IN  THE  DEVELOPMENT 
OF  THE  COAL-TAR  COLOUR  INDUSTRY 

I  have  narrated  this  chapter  of  industrial  chemical  history  in 
the  barest  outline,  because  the  details  can  be  filled  in  by  reference 
to  existing  literature.  But  I  have  spoken  of  nothing  of  which  I 
have  not  personal  recollection,  because  at  that  period  it  was  my 
regular  habit  to  keep  myself  acquainted,  as  far  as  was  made 


266         THE   BRITISH   COAL-TAR   INDUSTRY 

known  through  the  ordinary  channels  of  publication,  with  what 
was  going  on  in  the  colour  industry  outside  our  own  works,  and 
specimens  of  the  new  colouring  matters  sooner  or  later  found 
their  way  into  our  laboratory.  I  claim  therefore  with  some  con- 
fidence that  this  period  of  fifteen  years  was  not  only,  as  I  have  said, 
a  most  eventful  one,  but  it  may  even  be  permissible  to  go  further 
and  to  declare  that  it  was  the  most  critical  period  in  the  whole 
history  of  the  coal-tar  colour  industry.  It  was  the  period  which 
witnessed  the  introduction  of  nearly  all  the  chemical  types  of 
colouring  matters  on  the  market  at  the  present  time,  and  it  was, 
above  all,  the  period  which  saw  the  stagnation  and  the  commence- 
ment of  the  decay  of  the  British  coal-tar  colour  industry.  A 
careful  examination  of  the  history  of  this  period  should  therefore 
furnish  lessons  of  the  utmost  importance.  What  does  this  history 
reveal  ?  In  the  first  place,  the  broad  fact  that  there  was  immense 
activity  in  the  way  of  discovery,  and  in  the  next  place,  that  the  centre 
of  this  activity  was  not  in  this  country.  Consider  all  these  new 
types  of  colouring  matters  or  every  individual  dye  discovered 
during  the  period,  and  it  will  be  found  that  our  national  contribu- 
tion to  the  industry  was  quite  insignificant  as  compared  with  the 
foreign  and  especially  the  German  discoveries.  The  question  of 
the  cause  of  the  decline  of  the  British  industry  resolves  in  reality 
into  the  question  of  the  cause  of  the  Continental  activity. 

The  answer  to  this  last  question  has  been  staring  us  broadly 
in  the  face  for  over  thirty  years.  It  is  amazing  that  there 
should  have  ever  been  any  doubt  about,  or  any  other  cause 
suggested  than  the  true  cause,  which  is  RESEARCH — writ 
large  I  The  foreign  manufacturers  knew  what  it  meant  and 
realised  its  importance,  and  they  tapped  the  universities  and 
technical  high  schools  and  they  added  research  departments 
and  research  chemists  to  their  factories,  while  our  manufacturers 
were  taking  no  steps  at  all,  or  were  calmly  hugging  themselves 
into  a  state  of  false  security,  based  on  the  belief  that  the  old 
order  under  which  they  had  been  prosperous  was  imperishable. 
It  is  true  that  when  the  effects  of  the  new  discoveries  began 
to  make  themselves  felt,  one  or  two  factories  did  add  a  research 
chemist  to  the  staff,  but  the  number  and  the  means  of  work 
were  totally  inadequate.  I  happened  to  be  one  of  them,  and 
so  I  speak  with  some  practical  knowledge  of  the  conditions. 
We  were  but  a  handful  of  light  skirmishers  against  an  army 
of  trained  legionaries.  What  could  three  or  four — say  half 


TINCTORIAL   CHEMISTRY,   1870-1885         267 

a  dozen  at  a  liberal  estimate — research  chemists,  working  under 
every  disadvantage,  do  against  scores,  increasing  to  hundreds, 
of  highly  trained  university  chemists,  equipped  with  all  the 
facilities  for  research,  encouraged  and  paid  to  devote  their  whole 
time  to  research,  and  backed  up  by  technological  skill  of  the 
highest  order  ?  The  cause  of  the  decline  of  our  supremacy  in 
this  colour  industry  is  no  mystery — it  is  transparently  and 
painfully  obvious.  In  the  early  stages  of  its  decadence  it  had 
little  or  nothing  to  do  with  faulty  patent  legislation  or  excise 
restrictions  with  respect  to  alcohol.  The  decay  of  the  British 
industry  set  in  from  the  time  when  the  Continental  factories 
allied  themselves  with  pure  science  and  the  British  manufacturers 
neglected  such  aid,  or  secured  it  to  an  absurdly  inadequate 
extent  in  view  of  the  strength  of  the  competing  forces. 

It  has  often  been  asserted  that  the  British  colour  industry 
suffered  from  the  imperfection  of  our  patent  laws.  I  am  quite 
prepared  to  admit  that  there  is  some  justification  for  this 
contention  ;  our  patent  laws  were  faulty — they  are  by  no  means 
perfect  now — but  that  is  a  very  different  thing  from  the  assertion 
that  the  imperfection  of  the  patent  laws  was  the  main  cause 
of  our  decadence.  This  I  never  did  and  never  can  admit. 
The  history  of  that  fifteen-year  period  refutes  it.  I  say,  and 
always  have  said,  that  it  was  primarily  our  neglect  of  science 
which  was  responsible  for  our  stagnation,  in  precisely  the  same 
way  as  it  may  be  said,  per  contra,  that  it  was  the  appreciation 
of  science  which  was  the  cause  of  the  progress  of  our  competitors. 
Had  our  factories  been  creative  centres,  as  were  the  Continental 
factories — had  discoveries  of  great  industrial  value  been  pouring 
out  of  research  laboratories  here,  I  cannot  but  believe  that  the 
pressure  from  within  would  have  forced  the  hands  of  the 
legislature,  and  would  have  brought  about  an  amelioration  of 
the  patent  laws  long  ago.  Instead  of  attributing  the  decline 
of  our  colour  industry  to  the  imperfection  of  our  patent  laws, 
the  argument,  as  it  seems  to  me,  may  fairly  be  inverted,  and 
it  may  be  said  that  the  imperfection  of  our  patent  laws  was 
largely  due  to  our  want  of  initiative  in  colour  industry. 

TINCTORIAL  ART  AS  A  SCIENCE 

But  enough  has  been  said  to  enforce  the  lesson  that  the 
development  of  that  industry  which  chiefly  concerns  our  Society 


268         THE   BRITISH   COAL-TAR    INDUSTRY 

is  the  outcome  of  scientific  research.  And  what  is  true  for 
the  manufacture  of  those  materials  which  the  dyer  and  printer 
have  to  depend  upon  is  equally  true  for  the  development  of 
the  processes  for  applying  those  materials.  Tinctorial  art  is 
as  legitimately  a  subject  for  scientific  research  as  is  the  discovery 
of  new  colouring  matters.  The  processes  which  go  on  in  the 
dye  vat  are  still  under  investigation,  and  physical  and  chemical 
interpretations  of  results  which  are  of  everyday  experience  to 
the  practical  dyer  are  being  sought  by  many  scientific  workers 
pursuing  many  different  lines  of  attack.  This  Society  will  do 
well  to  keep  in  touch  with  this  work,  for  the  study  of  what  may 
be  called  the  "  inner  mechanism  "  of  dyeing  is  bound  up  with 
some  of  the  greatest  theoretical  questions  of  modern  physical 
chemistry.  There  is  in  this  field  another  point  of  contact 
between  science  and  industry  which  it  is  our  duty  to  keep  ever 
in  view.  Such  purely  abstract  questions  as  the  nature  of  the 
"  affinity  "  between  fibre  and  colouring  matter,  or  the  relation- 
ship between  colour  and  chemical  constitution,  which  are  now 
engaging  the  attention  of  some  of  the  leading  chemists  of  the 
time,  can  no  longer  be  ignored  by  the  so-called  "  practical  man." 
The  bearing  of  this  work  upon  practical  procedure,  if  not 
immediately  obvious,  is  as  certain  to  make  itself  felt  in  the 
future  as  were  the  speculations  of  Kekul6  and  the  researches  of 
the  chemists  of  his  time  upon  the  development  of  the  coal-tar 
colour  industry. 


XXL:    1910 

PATENT  LAW  IN  RELATION  TO  THE 
DYEING  INDUSTRY 

BY  A.  G.  BLOXAM,  F.I.C. 

(Journal  of  the  Society  of  Dyers  and  Co  lour  1st s^  1910,  p.  119) 

DURING  the  past  thirty  years  patent  law  has  been  of  great 
importance  to  the  dyeing  industry,  and  conversely  the  dyeing 
industry  has  been  of  great  importance  to  patent  law,  and  the 
industry  and  the  law  have  together  achieved  incidentally  a  much 
greater  result  than  their  mutual  benefit.  The  whole  of  organic 
chemistry  has  been  wondrously  advanced  by  the  desire  of  the 
maker  of  dyestuffs  on  the  one  hand  to  obtain  monopolies  of  new 
colours,  and  on  the  other  hand  to  avoid  paying  royalties  under 
existing  patents. 

The  annexed  curve  (fig.  3),  showing  the  number  of  patent 
specifications  relating  to  artificial  dyestuffs  of  each  year  during 
the  period  1855-1907,  is  not  without  interest. 

It  was  in  1856  that  the  artificial  dyestuff  industry  had  its 
birth.  No  doubt  picric  acid,  murexide,  and  one  or  two  other 
dyestuffs  were  made  artificially  prior  to  that  year  ;  I  have  not 
been  able  to  find  any  patents  for  their  manufacture  earlier  than 
1856  ;  their  existence  does  not  appear  to  have  led  to  any 
systematic  study  of  how  to  make  new  colours,  such  as  has  arisen 
since  Perkin's  Patent  No.  1984,  of  1856. 

The  curve  is  compiled  from  the  official  indexes  ;  the  indexer 
has  included  two  specifications,  prior  to  Perkin's,  as  relating  to 
artificial  dyestuffs.  One  of  these,  however,  deals  with  a  modified 
Prussian  blue,  and  the  other  with  a  mixture  of  albumen  and  a 
metallic  powder. 

269 


270         THE   BRITISH   COAL-TAR   INDUSTRY 


It  was  not  until  Renard  Freres  patented  fuchsine,  in  1859 
(No.  921/59),  that  the  growth  of  this  type  of  patent  became 
vigorous.  That  year  produced  a  crop  of  ten,  as  is  shown  in  the 
curve  relating  to  rosaniline  dyestuffs  (fig.  4).  I  should  have 
preferred  to  draw  this  curve  for  aniline  dyestuffs  generally,  but 
whereas  it  is  pretty  easy  among  the  earlier  patents  to  pick  out 
those  which  may  properly  be  said  to  deal  with  aniline  dyes,  it 


A/fZ7S7£Z4Z 


60     65    70     75    80    85 
FIG.  3. 


95    00     05 


becomes  almost  impossible  in  later  years  to  make  this  distinction, 
because  of  the  great  differentiation  that  has  occurred  between  the 
numerous  descendants  of  Perkin's  patent.  The  official  indexer 
has  classed  Perkin's  patent  in  the  azine  group,  so  that  this  patent 
is  not  recorded  in  the  rosaniline  curve. 

The  rosaniline  curve  attained  its  maximum  in  1863,  and 
then  declined  rapidly,  touching  zero  in  1868  and  again  in  1872 
and  1875.  It  will  be  seen  that  up  to  this  latter  year  the  artificial 
dyestuff  curve  and  the  rosaniline  curve  are  very  similar,  showing 


PATENT  LAW  IN  RELATION  TO  DYESTUFFS     271 

that  for  the  first  twenty  years  little  else  was  done  than  the  ringing 
of  the  changes  on  aniline  and  its  homologues.  The  differences 
between  the  rosaniline  curve  and  the  general  curve  up  to  this 
point  are  largely  due  to  the  anthracene  dyestuff  curve  (fig.  5), 


to 


1  55  60  65  70  75  80  85  90  95  00  05 

FIG.  4. 

which  sprang  into  being  with  Liebermann  and  Graebe's  Patent 
No.  3850,  of  1868,  for  the  manufacture  of  artificial  alizarin. 

There  were  also  a  few  specifications  relating  to  azo  dyestufFs 
in  this  period,  it  having  been  discovered  that  by  treating  amines 
with  nitrites,  dyestufFs  could  be  obtained  (fig.  6).  It  was  not, 


25 


15 
10 


AA 

A 

/fv 

A 

f\ 

TJ 

\ 

/ 

J 

vv 

/V 

2 

v 

55  60    66    70    75     86    85    90     95    00    0 

FIG.  5. 

however,  until  Griess's  Patent  No.  3698,  of  1877,  that  patenting 
received  the  fresh  blood  which  it  seemed  to  require.  It  was  in 
this  year  also  that  Germany  adopted  her  celebrated  patent  law, 
and  it  rapidly  became  the  custom  to  patent  in  this  country  all 
the  more  important  dyestufF  inventions  patented  in  Germany. 

Turning  to  the  curve  of  sulphurised  dyestufFs  (fig.  7),  Caro's 
Patent  No.  3751,  of  1877,  for  a  dye  of  the  methylene  blue  class 


272 


THE   BRITISH   COAL-TAR   INDUSTRY 


appears  to  have  been  the  first,  and  until  1884  all  the  dyes  thus 
classified  seem  to  have  been  of  this  type.  In  1884  Vignon  & 
Co.  patented  the  process  of  melting  paraphenylenediamine  with 
a  molecular  proportion  of  sulphur  and  oxidising  the  product  ; 
several  others  of  this  type  followed,  but  it  was  not  until  Vidal's 
Patent  No.  9443,  of  1894,  that  sulphurised  dyestuffs  really  made 
a  start.  From  1898  to  1899  they  jumped  from  fourteen  to 
forty-six,  an  increase  which  it  would  be  hard  to  rival  in  any 


50 
45 
40 
35 
30 
25 
20 
15 
10 
5 
0 


1865  60    65 


75     SO     85     90     95    0 

FIG.  6. 


r~o5 


subject-matter  unless  it  be  the  bicycle  class  ;  since  then,  however, 
they  have  steadily  declined,  falling  to  thirteen  in  1907. 

1880  was  the  year  of  Baeyer's  first  patent  (No.  1 177,  of  1880) 
for  making  indigo.  It  was  from  orthonitrophenylpropiolic  acid, 
and  it  did  not  prove  a  commercial  success.  Ten  years  passed 
before  the  Badische  Anilin-  und  Soda-Fabrik  patented  (Nos.  8726 
and  10,509,  of  1890)  the  phenylglycine  process,  really  due  to 
Heumann.  Even  then  patenting  did  not  become  general  until 
1898  ;  it  attained  its  maximum  in  1901,  and  is  now  on  the 
decline  (fig.  8). 

These  curves,  it  must  be  said,  only  partially  represent  the 
activity  in  the  industry.  As  I  have  already  mentioned,  they  are 
limited  to  specifications  which  profess  to  produce  the  respective 


PATENT  LAW  IN  RELATION  TO  DYESTUFFS     273 

dyestuffs.  Intermediate  products  are  not  included  unless  they 
are  described  in  the  same  specification  as  the  dyestuff.  In  the 
case  of  indigo  in  particular  this  makes  a  considerable  difference 


45 
40 
35 
30 
25 
20 
15 
10 
5 
0 


1855   60     65 


is  r  A 

FIG.  7. 


in  the  idea  one  obtains  of  the  extent  of  the  patenting  from  a  view 
of  the  curve  ;  a  large  part  of  the  work  expended  on  the  subject 
has  been  directed  to  the  manufacture  of  substances  destined  to 
be  finally  converted  into  the  dyestuff. 


15 
10 


f\ 

r 

IN 

L 

J\ 

w 

^ 

^A/\ 

j 

55  60    65    70     75 
Fie 

0    85    90    95    0      0 

r.    8. 

The  azo  dyestuff  curve  is  also  rather  a  poor  representation 
of  the  activity,  although  here  it  is  more  frequently  the  case  that 
intermediate  products  and  dyestuffs  are  described  in  the  same 
specification.  Probably  the  sulphurised  dyestuff  curve  is  most 
free  from  this  defect,  and  therefore  the  much  greater  number  of 

18 


274         THE   BRITISH   COAL-TAR   INDUSTRY 

patents  in  this  branch  is  not  so  remarkable  as  would  appear  at 
first  sight. 

Prior  to  1883  provisional  specifications  not  followed  by  a 
complete  specification  were  published,  and  are  included  in  the 
curves  ;  subsequent  to  that  date  only  complete  specifications 
have  been  published,  so  that  in  comparison  the  number  of  appli- 
cations appears  smaller. 

The  maximum  of  patenting  coincides  with  the  maximum  of 
sulphurised  dyestuffs,  and  the  heavy  decline  of  the  latter  during 
the  past  ten  years  has  been  accompanied  by  a  serious  decline  in 
the  total  number  of  patents  ;  however,  there  has  been  a  distinct 
recovery  since  1903,  due  chiefly  to  the  increased  demand  for  lakes. 

The  last  decade  of  the  nineteenth  century  was  certainly  one 
of  marvellous  synthetic  activity  ;  probably  we  shall  see  the  like 
again,  but  in  what  direction  it  is  not  easy  to  prophesy.  Indigo 
having  succumbed,  there  does  not  seem  to  be  any  natural  dyestufF 
worthy  of  sustained  attack  from  the  technical  standpoint.  Some 
life  is  at  present  (1910)  exhibited  by  dyestuffs  of  the  anthracene 
series,  but  otherwise  the  industry  may  be  said  to  be  resting. 

It  is  a  matter  of  some  surprise  that  the  manufacturers  have 
been  so  eager  to  patent  their  dyestuffs.  Where  successful  secret 
working  is  possible  the  monopoly  may  be  much  longer  than  that 
afforded  by  a  patent,  and  far  less  troublesome  in  many  respects. 

Fortunately  for  the  industry  and  for  science,  the  manu- 
facturers have  preferred  to  patent ;  it  is  sincerely  to  be  hoped 
that  they  will  continue  to  do  so,  for  no  thoughtful  man  can  fail 
to  realise  the  immense  benefit  which  must  accrue  from  a  system 
by  which  inventors  are  given  every  encouragement  to  pour  their 
inventions  into  the  lap  of  the  public,  notwithstanding  that  there 
is  much  which  the  public  do  not  want.  Indeed,  this  must  be 
regarded  as  the  reasonable  basis  for  a  patent  law. 

Abolitionists  in  respect  of  patent  laws  are  practically  extinct. 
Switzerland  has  succumbed,  now  granting  patents  not  merely  for 
embodied  inventions,  but  for  processes.  Holland  abandoned 
her  fifty-year-old  law  in  1869,  but  is  now  about  to  legislate  again 
in  favour  of  patents. 

It  cannot  be  gainsaid  that  industry  benefits  enormously  by 
the  publication  of  inventions  ;  the  intended  benefit,  namely,  that 
the  public  may  know  how  to  exercise  the  invention  at  the  expira- 
tion of  the  term  of  the  grant,  is  small  compared  with  the  stimulus 
given  to  fresh  invention,  not  merely  by  leading  the  reader's 


PATENT  LAW  IN  RELATION  TO  DYESTUFFS     275 

mind  into  fresh  fields  of  thought,  but  by  the  desire  suggested 
on  the  one  hand  to  "  go  one  better,"  and  on  the  other  hand  to 
evade  the  patent  claim.  This  direct  benefit  to  industry  may 
even  be  eclipsed  by  the  indirect  benefit  procured  through  the 
educational  value  of  the  publication.  Patent  specifications  are 
becoming  our  best  technical  journal,  albeit  one  in  which  much 
rubbish  is  printed. 

It  is  the  compulsory  and  immediate  publication  as  a  condition 
of  the  patent  grant  which  has  led  to  the  present  highly  developed 
state  of  the  artificial  dyestuff  trade  and  of  organic  chemistry. 

It  was  largely  due  to  the  representations  of  Mr  Levinstein 
that  the  Board  of  Trade  appointed  a  committee  at  the  end  of 
1900,  whose  report  gave  rise  to  the  Patent  Act  of  1902.  This 
provided  a  modification  of  the  compulsory  licensing  clauses 
(which  did  not  prove  satisfactory)  and  introduced  a  system  of  pre- 
liminary examination,  which  came  into  force  on  ist  January  1905. 

Five  years'  experience  of  the  working  of  this  system  has  not 
caused  me  to  vary  my  opinion  that  a  preliminary  examination  is 
not  advantageous  either  to  the  public  or  to  the  inventor.  The 
system  involves  a  search  among  specifications  to  British  patents 
published  during  a  period  of  fifty  years  prior  to  the  date  of  the 
patent  application  under  examination. 

A  few  years  hence,  when  a  considerable  number  of  the  patents 
dated  1905  and  onwards  have  come  before  the  courts,  we  shall 
be  in  a  position  to  judge  whether  the  preliminary  examination 
has  had  any  effect  in  enabling  the  patentee  to  place  more  reliance 
upon  his  patent.  I  am  not  hopeful  that  this  will  be  the  case. 
So  far  six  patents  which  have  been  subjected  to  preliminary  ex- 
amination have  been  before  the  courts,  and  of  these  only  two 
were  upheld  as  valid. 

As  I  have  already  stated,  patents  ought  to  be  granted  primarily 
for  the  purpose  of  informing  the  public  how  new  manufactures 
are  to  be  conducted.  1  think  there  is  sometimes  a  slight  con- 
fusion of  ideas  as  to  the  nature  of  the  reward  which  is  supposed 
to  be  bestowed  on  the  inventor  by  the  patent  grant.  I  take  it 
that  the  reward  is  a  recompense  to  the  inventor  for  disclosing  the 
manufacture  ;  it  is  one  which  must  depend  entirely  on  his  own 
exertions,  since  the  sole  profit  which  he  can  reap  is  in  working 
the  invention  himself  or  persuading  others  to  work  on  a  royalty. 
The  reward  is  not  one  for  establishing  a  new  industry  or  manu- 
facture. The  difference  seems  to  me  considerable  ;  in  the  one 


276        THE   BRITISH   COAL-TAR   INDUSTRY 

case  the  contract  between  the  public  and  the  inventor  is  that  he 
shall  have  the  sole  right  to  endeavour  to  establish  the  manufacture 
and  to  continue  the  manufacture  if  established.  In  the  other  case, 
the  contract  would  be  that  the  inventor  should  have  the  sole 
right  to  manufacture  when  the  manufacture  had  been  established. 
Provisions  as  to  immediate  publication  would  be  useless  in  the 
latter  case,  and,  indeed,  injurious  both  for  the  public,  as  rerfdering 
it  less  likely  that  the  manufacture  would  be  established,  and  to 
the  inventor,  as  telling  all  his  competitors  in  what  direction  he 
was  endeavouring  to  obtain  the  patent  reward.  Publication 
would  not  be  necessary  until  after  the  establishment  of  the 
manufacture,  and  then  only  for  the  purpose  of  defining  the  pro- 
tection afforded  by  the  patent. 

The  patent  grant  as  a  recompense  for  publication  ensures 
that  there  shall  be  no  chance  of  the  public  losing  the  increased 
convenience,  comfort,  and  economy  due  to  the  ingenuity  of  the 
inventor.  At  the  same  time  it  is  inexpedient  that  the  inventor 
should  be  allowed  to  sit  on  his  patent  rights,  and  thus  delay  the 
public  enjoyment  of  the  fruits  of  his  invention  for  the  whole,  or 
a  considerable  part,  of  the  term  of  his  patent. 

Partly  for  the  purpose  of  checkmating  the  dog-in-the-manger 
patentee,  many  countries  adopted  what  is  known  as  compulsory 
working,  the  patent  becoming  automatically  void  after  a  few 
years  if  not  worked  in  the  country.  This  is  a  very  severe 
measure  ;  the  number  of  patentees  who  need  chastisement  for 
declining  to  work  their  patents  is  relatively  very  small  ;  the  great 
majority  of  patentees  yearn  to  have  their  patents  worked,  and 
spend  much  labour  in  endeavouring  to  get  them  worked.  Re- 
garded as  a  measure  against  the  dog-in-the-manger,  this  system 
has  never  found  favour  in  our  country. 

On  the  other  hand,  the  compulsion  to  grant  licences  on 
reasonable  terms  when  requested  to  do  so  appears  free  from 
objection,  and  this  mode  of  meeting  the  objection  under  con- 
sideration has  been  steadily  put  forward  ever  since  the  beginning 
of  the  last  century.  The  difficulty  of  determining  what  should 
be  the  conditions  precedent  to  the  compulsory  licence  seems  to 
have  been  the  obstacle  in  the  way  of  the  adoption  of  the  mode, 
and  it  was  not  until  the  Act  of  1883  that  any  provision  found 
its  way  into  our  law.  The  difficulty  is  not  yet  settled,  however, 
since  the  amending  Acts  of  1 902  and  1 907  have  both  varied  the 
original  conditions 


PATENT  LAW  IN  RELATION  TO  DYESTUFFS     277 

No  system  of  compulsory  licensing  or  compulsory  working 
exists  in  the  United  States.  Personally  I  am  disposed  to  think 
that  the  system  of  compulsory  licensing  should  be  carried  much 
further  than  has  been  done  in  any  country  within  my  knowledge. 
Why  should  it  not  be  incumbent  upon  the  patentee  to  grant 
licences  to  all  comers  ?  If  he  has  spent  time  and  capital  in 
setting  up  a  manufacture  of  the  invention  before  he  is  asked  to 
grant  a  licence,  this  fact  must  be  taken  into  consideration  in 
settling  the  royalty.  The  patentee  should  have  the  opportunity 
of  being  first  in  the  field  ;  it  would  be  only  right  that  he  should 
not  be  compelled  to  grant  a  licence  until  his  patent  was  of  a 
certain  age.  I  do  not  see  why  the  requirements  of  the  public  or 
the  public  interest — factors  which  it  is  always  difficult  to  de- 
termine— should  come  into  consideration. 

Whatever  system  of  compulsory  licensing  be  ultimately 
adopted,  I  am  convinced  that  it  will  be  found  an  adequate 
substitute  for  compulsory  working,  not  only  in  respect  of  pre- 
venting the  patent  from  becoming  a  true  monopoly,  but  also  in 
respect  of  enforcing  as  far  as  possible  the  working  of  the  patent 
in  the  country  of  origin. 

To  some  extent  compulsory  working  is  a  corollary  of  pro- 
tective tariffs.  No  amount  of  duty  on  an  imported  patented 
article  could  serve  to  establish  the  manufacture  of  it  if  the 
patentee  had  the  power  to  veto  the  manufacture.  Even  in  a 
protectionist  country,  however,  the  policy  of  penalising  non- 
working  by  revocation  of  the  patent  is  suicidal,  so  far  as  the 
establishment  of  the  manufacture  is  concerned.  Those  who 
advocate  this  penalty  are  strangely  illogical  ;  the  patent  was 
granted,  they  say,  to  establish  a  new  manufacture  because  no  one 
will  embark  capital  in  such  an  enterprise  without  some  protection 
from  competition.  If  the  manufacture  is  not  established  within 
a  certain  period  they  would  proceed  to  extinguish  the  sole  in- 
centive for  establishing  it. 

At  least  the  revocation  should  not  occur  until  someone  is 
ready  to  work  the  invention.  The  position  would  be  less  absurd 
if  it  were  essential  for  the  person  applying  for  revocation  to 
show  that  he  is  ready  to  start  the  manufacture,  and  has  a  reason- 
able prospect  of  an  extensive  trade. 

To  my  mind,  however,  the  greatest  danger  in  the  system  of 
revocation  for  not  working  lies  in  the  fact  that  it  is  just  the 
patents  which  we  require  most  that  are  most  liable  to  revocation 


278         THE   BRITISH   COAL-TAR   INDUSTRY 

on  this  ground.  It  is  the  patent  which  it  is  difficult  to  work  in 
this  country  that  is  most  likely  to  establish  a  new  industry  ;  the 
revocation  of  the  patent  will  only  enhance  the  difficulty  of 
establishing  the  new  industry.  Hence  inventors  of  the  more 
revolutionary  inventions  will  refrain  from  patenting  them  until 
such  time  as  they  think  there  is  an  opportunity  of  manufacture 
being  started.  This  will  greatly  retard  the  progress  due  to  early 
publication  and  the  rivalry  already  alluded  to. 

After  all,  the  inventor  is  granted  the  patent  in  consideration 
of  his  having  introduced^  that  is,  disclosed,  the  manufacture,  not  of 
his  having  established  it.  And  in  practice  this  is  how  it  happens, 
almost  universally.  The  inventor  gets  his  reward  from  the  capital- 
ist before  the  manufacture  is  established  ;  it  is  the  capitalist  who 
reaps  a  reward  for  having  established  the  manufacture. 

If  patents  are  possessed  by  foreigners  in  order  that  they  may 
have  a  monopoly  of  importing  into  this  country,  the  evil — as  I 
will  call  it,  though  I  am  far  from  convinced  that  it  matters  to  the 
country — is  remediable  by  allowing  Britishers  or  other  foreigners 
to  obtain  easily  a  licence  for  importing.  If  such  patents  are  held 
for  the  purpose  of  preventing  manufacture  in  this  country,  a 
compulsory  licence  will  also  serve  as  a  cure. 

DISCUSSION 

Dr  CAIN  drew  attention  to  the  difficulty  of  keeping  the  manu- 
facture of  dyestuffs  secret,  as  had  been  suggested  by  Mr  Bloxam. 
He  mentioned  the  case  of  primuline.  The  manufacturer  of 
this  dyestuff  declined  to  take  out  a  patent  and  decided  to  keep 
the  process  a  secret.  Being  the  first  of  an  entirely  new  class  of 
dyestuffs  and,  moreover,  there  being  considerable  difficulty  in 
ascertaining  by  analysis  its  chemical  constitution,  it  was  thought 
that  there  would  be  no  difficulty  in  keeping  the  matter  quite 
secret.  Unfortunately,  three  weeks  after  the  introduction  on 
the  English  market  of  this  particular  colour  a  similar  colour 
was  put  on  the  market  by  a  German  firm.  He  thought  that  in 
the  case  of  sulphurised  dyestuffs  there  would  be  less  difficulty 
in  keeping  the  matter  secret.  He  was  of  opinion  that  the  cost 
of  applying  for  compulsory  licences  for  the  working  of  patents 
in  this  country  was  the  reason  of  their  not  being  applied  for. 
With  reference  to  the  so-called  downfall  of  the  chemical  industry 
in  England,  he  mentioned  the  fact  that  Hofmann  had  often  been 


PATENT  LAW  IN  RELATION  TO  DYESTUFFS     279 

credited  with  the  invention  of  coal-tar  colouring  matters,  to 
which  he  was  not  strictly  entitled  ;  for  example,  Nicholson  pre- 
pared a  number  of  products  which  were  handed  over  to  Hofmann. 
Nicholson  by  phenylating  rosaniline  naturally  suggested  to  a 
chemist  the  methylating  of  the  same  product,  the  latter  producing 
Hofmann's  violet. 

Mr  W.  P.  DREAPER  defended  the  British  system  of  chemical 
training  as  compared  with  the  Continental,  and  thought  it  was 
more  conducive  to  freedom  of  thought.  In  his  opinion  the 
number  of  individual  thinkers  turned  out  in  England  was  much 
greater  than  was  the  case  on  the  Continent.  He  thought  that 
compulsory  search  was  to  the  advantage  of  the  inventor,  as  he 
was  thereby  enabled  to  go  direct  to  the  Patent  Office  and  not 
necessarily  pass  his  invention  through  the  hands  of  an  agent. 

Dr  E.  FEILMANN  thought  that  the  working  of  compulsory 
licences  might  be  settled  in  a  businesslike  manner,  without 
calling  in  the  Law  Officers  of  the  Crown,  the  terms  being 
arrived  at  by  the  ordinary  method  of  business  bargaining,  with- 
out any  interference  on  the  part  of  paid  officers. 

Mr  BLOXAM,  in  reply,  expressed  the  opinion  that  the  granting 
of  compulsory  licences  ought  not  to  be  anything  like  so  costly  as 
was  the  case  at  present.  He  pointed  out  that  the  average  dye- 
stuff  patent  covered  many  hundreds  of  dyestuffs,  and  it  was  not 
necessary  to  limit  the  specification  to  one  particular  dyestuff,  as 
was  the  case  in  the  United  States.  He  referred  to  the  fact  that 
in  the  case  of  Levinstein,  the  Board  of  Trade  made  an  order  to 
grant  a  licence,  but  no  licence  was  actually  granted. 


XXIL:    1910 

THE  COAL-TAR  COLOUR  INDUSTRY  OF 

ENGLAND:    CAUSES    OF    ITS    PROGRESS 

AND    RETARDATION 

BY  I.  SINGER 

(Journal  of  the  Society  of  Dyers  and  Colourists,  1910,  pp.  124—150) 

THE  question  "  Why  did  not  the  coal-tar  industry  obtain  a  sure 
and  permanent  footing  in  the  land  of  its  birth,  and  why  has  it 
reached  such  perfection  and  development  in  Germany  ? "  has 
often  been  asked  and  variously  answered,  according  to  the 
standpoint  of  the  critic  or  the  occasion  which  called  forth  the 
reflection. 

In  this  country  the  high  excise  duty  on  alcohol,  the  patent 
laws,  high  wages,  the  free-trade  policy,  want  of  adequate  second- 
ary education,  the  supposed  absence  of  research  chemists,  have 
all  been  mentioned  in  turn  as  being  concerned  in  obstructing  the 
development  of  the  colour  industry. 

In  Germany,  however,  entirely  different  views  prevail.  There 
it  is  boldly  asserted  that  inasmuch  as  the  coal-tar  industry  is 
essentially  of  a  scientific  character,  it  as  naturally  was  bound  to 
become  a  German  industry. 

It  was  to  be  expected  of  their  patriotism  that  Germans  should 
accept  this  explanation  as  satisfactory  and  all-sufficient,  but  it 
caused  no  little  surprise  in  other  countries  where  the  problem 
has  been  discussed  with  as  keen  an  interest,  perhaps,  as  in 
Germany  itself,  albeit  it  has  not  been  viewed  through  German 
spectacles. 

This  is  probably  the  reason  why  the  editors  of  the  Vegvhzeti 
JLapok — the  official  organ  of  the  Hungarian  Association  of 
Chemical  Industry — have  asked  me  to  state  the  views  entertained 

280 


CAUSES  OF  PROGRESS  AND  RETARDATION     281 

in  this  country  concerning  this  question.  "We  know,"  they 
wrote,  "that  the  Germans  have  written  a  great  deal  on  this 
subject,  but  we  think  it  would  interest  our  readers  to  have  an 
impartial  statement  of  the  opinions  of  the  British  consumers." 

I  responded  to  this  appeal  with  an  article  which  appeared  in 
the  Christmas  number  of  the  Vegveszeti  Lapok.  I  did  not 
attempt,  however,  to  interpret  the  views  of  others,  but  gave  my 
own.  In  this  article,  originally  intended  for  Hungarian  readers 
only,  I  tried  to  disprove  certain  allegations  which,  through  per- 
sistent reiteration  rather  than  any  inherent  merits,  have  gained 
currency  abroad  ;  allegations  which  ascribed  German  supremacy 
in  this  particular  industry  to  the  special  aptitude  of  Germans  for 
scientific  pursuits,  and,  inferentially,  affirmed  the  want  of  it  in 
this  country. 

I  pointed  out  not  only  the  inadequacy,  but  the  absurdity  of 
this  explanation,  and  tried  to  show  that  the  problem  itself  was 
neither  fairly  nor  correctly  stated,  inasmuch  as  many  of  the 
assumed  facts  could  be  shown  to  be  untrue  or  exaggerated. 

I  hoped  the  matter  would  end  there  as  far  as  I  was  con- 
cerned, but  in  this  I  was  mistaken.  An  abstract  of  my  article 
appeared  in  the  Chemical  Trade  Journal  (i$th  January),  and  thence 
found  its  way  into  The  Times  (9th  February)  as  an  addendum  to  a 
contributed  article  on  "  Research  Chemists."  Both  these  journals 
were  of  opinion  that  my  facts  and  arguments  deserved  some 
attention.  The  Chemiker  Zeitung  of  Coethen,  however,  is  of 
quite  the  opposite  opinion,  and  is  very  wroth  indeed  with  the 
English  Press  for  its  indiscretion  in  taking  notice  of  such  abomin- 
able heresies,  since  this  compelled  them  to  notice  the  article 
themselves. 

The  most  common  idea  is  that  England  has  lost  the  "coal-tar 
colour  industry  through  want  of  capable  chemists.  This  opinion 
finds  expression  in  different  forms.  Even  in  this  country  com- 
plaint is  made  that  not  sufficient  attention  is  paid  to  chemical 
research.  The  opinion  seems  to  prevail  that  if  more  research 
work  were  carried  on,  a  larger  share  of  the  chemical  industries 
would  be  secured  for  this  country. 

In  dissenting  from  this  view,  I  do  not  wish  to  be  understood 
that  I  intend  to  disparage  research  work  of  any  kind.  Far  from 
it.  The  more  there  is  of  it  the  better,  provided,  of  course,  that 
the  means  could  be  found  to  compensate  those  who  would  devote 
themselves  to  the  task. 


282         THE   BRITISH   COAL-TAR   INDUSTRY 

In  Germany  they  smile  at  the  idea  of  England  ever  com- 
peting successfully  in  the  organic  chemical  industries,  because, 
they  aver,  it  is  a  pursuit  which  can  thrive  only  in  the  hands 
of  a  scientifically  gifted  nation.  They  are  quite  sincere  in  be- 
lieving that  they  possess  special  aptitudes  for  work  which  requires 
deep  thinking,  careful  and  patient  application,  and  regard  the 
conquest  of  this  industry  by  Germans  for  Germany  as  a 
crowning  proof  of  "  German  thoroughness  "  and  "  German  in- 
tellectuality." 

This  belief  was  interpreted  with  sufficient  clearness  by  Dr 
Duisberg  at  the  Perkin  Jubilee  banquet  in  the  following  words  : 
"  No  other  industry  requires  so  much  uniformity  of  thought  and 
action,  science  and  practice,  as  organic  chemistry  or  organic- 
chemical  industry.  .  .  .  We  Germans  possess  in  a  special  degree 
this  quality  of  working  and  waiting  at  the  same  time,  and  of 
taking  pleasure  in  scientific  results  without  technical  success." 

I  could  quote  much  more  to  the  same  effect,  but  this  should 
be  sufficient.  Nor  would  I  have  noticed  this  delicious  specimen 
of  national  self-appreciation  were  it  not  that,  through  constant 
reiteration,  people  even  in  this  country  have  become  infected  by 
the  belief  that  Germany  has  the  command  of  this  industry 
because  of  her  superior  education,  and  that  if  this  country  only 
produced  more  chemists,  she  would  thereby  secure  a  larger  share 
of  the  colour  industry. 

Now  it  is  not  necessary  to  question  German  genius  or 
German  achievements  in  whatever  field  of  activity,  nor  to  put 
forth  rival  claims  on  behalf  of  the  British  people  before  one 
may  dissent  from  such  opinions. 

The  most  superficial  reflection  must  disclose  the  absurdity  of 
any  suggestion  that  England  has  lost  the  coal-tar  industry  for 
want  of  sufficient  acumen,  or  that  the  industry  owes  its  present 
ramifications  solely  and  entirely  to  German  intelligence  and 
industry. 

To  guard  against  any  possible  misunderstanding,  I  hasten 
to  make  clear  my  meaning.  In  the  above  sentence  I  do  not 
allude  to  the  share  of  the  work  which  chemists  all  over  the 
world,  and  of  every  nationality,  had  in  making  organic  chemistry 
what  it  is  to-day  ;  nor  do  I  intend  to  belittle  the  intelligence 
and  industry — admitted  and  admired  the  world  over — which 
Germans  have  displayed  in  its  industrial  application.  They 
have  worked  well ;  their  results  are  as  brilliant  as  they  are  well 


CAUSES  OF  PROGRESS  AND  RETARDATION     283 

earned.  But  what  I  wish  to  insist  upon  is  this,  that  all  the 
intellect  and  industry  of  a  nation,  however  great,  could  not 
possibly  have  made  the  coal-tar  industry  into  what  it  is  to-day 
but  for  the  inherent  potentiality  of  the  germ.  As  well  ascribe 
the  widely  diffused  application  of  steam  power,  of  electricity,  of 
railways,  or  the  telephone  to  the  "  intelligence  and  industry  "  of 
this  or  that  nation. 

In  modern  organic  chemistry  and  organic  syntheses  a  new 

principle    of    wide   application    has   been    discovered,    and   the 

enormous  ramifications  of  this  new  industry  must  be  ascribed  to 

this  fact,  and  not  to  this  or  that  nationality,  even  though  it  were 

—which  it  is  not — the  monopoly  of  a  particular  race. 

Great  and  rapid  as  has  been  the  growth  of  the  coal-tar 
industry,  it  has  not  been  more  so  than  the  spread  of,  say, 
electricity,  the  telephone,  the  automobile,  the  typewriter,  or  any 
number  of  industries  that  might  be  mentioned.  All  these  have 
grown  rapidly  to  immense  proportions  because  they  supplied  a 
human  want,  because  of  their  inherent  potentialities,  and  not 
because  of  the  nationality  of  the  people  who  were  instrumental 
in  their  creation. 

Nor  is  it  quite  correct  if — leaving  nationality  out  of  the 
question — we  credit  the  chemists  with  the  creation  of  this 
industry,  any  more  than  if  we  credited  the  electricians  with  the 
creation  of  the  electrical  industries.  At  least  it  is  as  true  to 
say  that  these  industries  have  called  into  being  the  chemists  and 
the  electricians  respectively,  as  that  the  latter  have  created  the 
former.  The  fact  is  that  the  chemists  and  the  industry-  have 
created  and  stimulated  each  other,  and  the  secret  cause  of  their 
success  is  the  great  demand  for  their  products. 

This  insistence  on  a  clear  perception  of  the  basic  facts  does 
not  in  the  least  lessen  the  merits  of  our  German  confreres  ;  it 
merely  brings  the  different  points  involved  into  their  true  per- 
spective. The  Germans  are  known  for  thoroughness  in  every- 
thing they  do.  They  are  as  intent,  as  industrious,  and  as 
scientific  in  their  shipbuilding,  their  navigation,  their  spinning 
and  weaving,  as  they  are  in  their  colour  making,  and  in  time 
may  possibly  eclipse  their  British  cousins  in  all  these  industries. 
But  they  have  not  done  so  yet.  Would  it  not  be  absurd  to 
ascribe  this  superiority  in  particular  industries  to  greater  intelli- 
gence in  the  British,  or  want  of  scientific  attainment  or  thorough- 
ness on  the  part  of  the  Germans  ? 


284         THE   BRITISH   COAL-TAR   INDUSTRY 

For  it  is  yet  to  be  proved  that  more  skill,  science,  or  patience 
is  required  to  make,  say,  benzopurpurine,  than  to  build,  let  us 
say,  a  Leviathan  (with  its  hundreds  of  details  so  carefully  ad- 
justed), a  Jacquard  loom,  a  combing  machine,  or  that  miracle  of 
mechanism — a  spinning  mule. 

It  is  begging  the  whole  question  to  say  that  England  has 
not  progressed  in  the  coal-tar  industry  because  she  has  not  the 
chemists  necessary  for  its  cultivation. 

Germany  did  not  have  them  fifty  years  ago.  If  she  has  them 
to-day  it  is  because  the  ever-expanding  industry  has  called  them 
into  being.  And  if  England  has  not  to-day  as  many  chemists  as 
Germany  trained  in  the  organic  chemical  industries,  it  is  because 
there  is  no  demand  for  them.  Had  they  been  wanted  the  supply 
would  have  been  forthcoming.  The  nation  which  produced  men 
like  Boyle,  Dalton,  Davey,  Graham,  Priestley,  Kelvin,  Faraday, 
Darwin,  Tyndall,  Huxley,  Babbage,  Arkwright,  Stephenson, 
Watts,  Bessemer,  Cartwright,  Ramsay,  Dewar,  Perkin,  Meldola, 
and  a  host  of  others  famous  in  science,  art,  and  literature,  might 
conceivably  have  supplied  men  capable  of  being  taught  how  to 
sulphonate  a  phenol  or  diazotise  an  amine — as  in  point  of  fact 
she  has  done  to  the  full  extent  of  her  requirements. 

But  the  contention  is  too  absurd  and  self-contradictory  for 
serious  argument.  For  by  a  similar  process  of  reasoning  might 
be  proved  German  incompetency  in  respect  of  such  arts  or 
industries  in  which  they  are  excelled  by  other  nations. 

Another  popular  misconception  is  that  England  has  lost  the 
colour  industry,  or  that  the  industry  has  retrogressed.  Phrases 
implying  one  or  the  other  are  constantly  met  with  both  here  and 
abroad,  without  anyone  ever  deeming  it  necessary  to  prove  such 
assertions.  It  is  simply  stated  and  accepted  as  common  know- 
ledge. It  is  a  common  experience,  however,  that  few  things  are 
in  greater  need  of  careful  investigation  and  confirmation  than 
the  "  facts  "  which  "  everybody  "  knows.  Most  of  the  assump- 
tions connected  with  the  problem  under  discussion  belong  to 
this  class,  and  should  be  looked  into  before  acceptance.  With 
this  object  in  view  let  us  look  at  a  few  facts  which  are  none  the 
less  true  because  everybody  does  not  seem  to  know  them.  One 
of  these — generally  forgotten — is  that  the  crude  product,  the 
coal  tar,  has  to  undergo  many  transformations  before  it  becomes 
a  colouring  matter,  and  that  at  each  successive  stage  of  manu- 
facture value  is  added  to  the  product.  Now  a  large  part  of  these 


CAUSES  OF  PROGRESS  AND  RETARDATION     285 

preliminary  and  intermediary  processes  are  performed  in  England 
on  a  very  extensive  scale,  and  such  products  have  been,  and  still 
are,  exported  to  Germany  and  other  countries.  That  such 
exports  are  not  negligible  quantities  may  be  seen  from  the 
following  return  for  last  year  : — 


British  Exports. 

British  Imports. 

Raw  and  intermediary  products     . 
Sundry    coal-tar     products     (including 
calcium  carbide) 
Indigo,  synthetic  ..... 
Colouring  matters          .... 

Total    .... 

£ 

1,630,000 
3,007,000 

341,000 

£ 

95,000 
2,319,000 

117,000 
1,803,000 

4,978,000 

4,334,000 

Excess  of  exports  . 

4,334,000 

644,000 

So  that  last  year  the  United  Kingdom  produced  ^644,000 
worth  of  coal-tar  products  more  than  her  own  not  inconsiderable 
requirements. 

This  has  been  true  all  along  the  whole  period  of  the  coal-tar 
industry.  That  is,  expressed  in  money  value,  this  country  has 
always  produced  more  than  the  value  of  her  own  requirements, 
though  some  products  she  imported  whilst  others  she  exported. 

Let  me  state  here  another  indisputable  fact,  though  not 
always  remembered  by  those  who  talk  about  the  "  loss  "  of  the 
industry,  or  of  its  retrogression,  and  that  is  that  at  no  time, 
from  the  inception  of  the  coal-tar  industry  to  this  day,  was  there 
any  retrogression.  Quite  the  contrary  ;  every  succeeding  year 
the  total  output,  whether  in  coal-tar  products  generally  or  in 
finished  colouring  matters,  was  greater  than  in  the  preceding 
year,  and  is  to-day  greater  than  at  any  previous  time. 

There  can  be  no  question,  therefore,  as  regards  the  progress 
of  the  industry  in  this  country,  though  that  progress  may  possibly 
not  be  comparable  to  that  of  Germany. 

But  even  here  we  are  in  need  of  information  before  we  can 
say  that  the  coal-tar  industry  as  a  whole,  as  distinct  from  that 


286         THE   BRITISH   COAL-TAR  INDUSTRY 

of  the  finished  dyestuff,  has  flourished  more  in  Germany  than  in 
this  country. 

I  have  no  data  to  prove  the  contrary,  yet  I  should  not  admit 
this  contention  until  some  proof  were  forthcoming.  I  will  state 
my  reasons. 

In  1890  Gustav  Schultz,  in  his  Chemie  des  Stein-kohlen- 
theers^  gave  the  following  statistics  of  the  quantities  of  tar 
distilled  for  the  purpose  of  colour  making  in  the  five  principal 
countries  of  Europe  : — 

England       .     400,000  tons      Germany  .  .  .  65,000  tons 

France  .  .  .  60,000    „ 

Belgium  .  .  .  50,000    „. 

Holland  .  .  .  15,000    „ 


Total       .         .     190,000  tons 

Thus  in  1890  England  contributed  more  than  twice  as  much 
as  all  the  other  countries  put  together.  As  already  mentioned, 
this  quantity  of  tar  did  not  leave  the  country  as  such,  but  was 
worked  up  into  hydrocarbons,  bases,  acids,  sulpho  and  nitro 
compounds — in  fact,  the  manufacturing  process  was  pushed  on  as 
far  as  British  industrial  conditions  permitted  this  to  be  done 
profitably.  True,  none  of  these  fall  under  the  designation  of 
"  colours,"  but  they  certainly  form  an  integral  and  essential 
part  of  the  "  coal  tar  "  industry. 

My  point  is  this,  that  whilst  the  manufacture  of  these  pro- 
ducts has  increased,  their  export  has  decreased.  A  private 
communication  to  the  writer  by  a  member  of  a  firm  who  are 
among  the  largest  makers  of  these  products,  explains  this,  as 
follows  : — 

"  I  am  very  sorry  I  cannot  give  you  the  figures  you  want 
with  reference  to  the  amount  of  raw  materials  exported  from 
England  to  Germany  in  recent  years,  nor  the  amount  of  dyes 
which  are  returned  to  this  country  made  from  such  raw  materials. 
There  are  no  available  statistics  for  either  of  these  figures. 

"The  export  of  intermediate  and  raw  products  to 
Germany  for  aniline-dye  manufacture  has  greatly  decreased 
during  the  last  few  years,  owing  to  the  fact  that  a  larger  pro- 
portion of  these  raw  materials  is  required  for  use  in  England. 
The  production  of  aniline  dyestuffs  in  England  has  greatly 
increased,  while  the  production  of  raw  materials  has  not.  In 
many  instances  the  English  works  have  nothing  to  spare  of  raw 


CAUSES  OF  PROGRESS  AND  RETARDATION     287 

materials,  where  they  were  formerly  anxious  to  export.  A 
further  reason  for  this  diminution  is  to  be  found  in  the  formation 
of  the  large  German  combines,  who  have  sought  to  make  them- 
selves entirely  independent  of  the  English  supplies  of  raw 
materials." 

Two  facts  are  here  confronting  us.  Germany  is  less 
dependent  now  for  her  raw  material  on  England,  and  the 
exports  of  such  products  from  this  country  have  decreased. 
But  .this  does  not  mean  that  less  of  them  is  produced,  for  the 
contrary  is  the  fact.  What  becomes  of  them  ?  The  answer 
is  partly  supplied  in  the  letter  1  have  just  quoted  : — "A  larger 
proportion  of  these  materials  is  required  for  use  in  England, 
since  the  production  of  aniline  dyestuffs  in  England  has  greatly 
increased." 

I  am  aware  that  the  British  exports  of  finished  dyestuffs  is 
insignificant  as  compared  with  those  from  Germany.  But  these 
sums  would  not  be  a  true  measure  of  comparison.  To  these  we 
should  have  to  add  the  values  of  domestic  consumption,  which  in 
England  is,  of  course,  incomparably  larger  than  in  Germany. 

But  do  not  let  us  lose  sight  of  the  main  issue  through  these 
comparisons.  My  object  is  not  to  contend  that  England's 
share  in  the  colour  industry  is  satisfactory.  I  merely  want  to 
show  that  the  past  and  present  agitation  having  for  its  object 
the  expansion  of  this  industry  is  proceeding  on  wrong  lines 
and  in  wrong  directions,  and  that  because  of  the  many  false 
assumptions. 

What  then  are  the  actual  facts  ? 

1.  That  this  country  has  a  large  and  flourishing  and  growing 
coal-tar  industry. 

2.  That  it  has  also  a  colour  industry,  which  has  never  yet 
lost   ground,  but    has    steadily  been    advancing,  and   is   to-day 
greater  than  at  any  previous  period. 

3.  That  England  not  only  more  than  supplies  her  own  wants 
in    coal-tar  products ,  but  even  in   finished    dyestuffs    consumed 
the  major  portion  is  locally  made. 

4.  That   some    dyestuffs   are   produced  in    this   country  in 
larger  quantities  than  in  Germany. 

5.  That    whilst    some   of   the    colouring    matters    that  have 
been  invented  in  England  are  neglected  here  in  comparison  with 
Germany,  others  that  have  been  invented  abroad  are  successfully 
manufactured  here. 


288         THE   BRITISH   COAL-TAR   INDUSTRY 

In  view  of  such  facts  we  can  no  longer  allow  ourselves  to  be 
misled  by  such  questions  as  "  Why  has  England  lost  the  colour 
industry  ? "  or  "  Why  has  the  colour  industry  migrated  from 
England  to  Germany  ?  "  and  so  forth.  Such  leading  questions 
affirm  far  more  than  they  ask  and  prejudice  the  whole  problem. 

It  is  not  a  fact  that  the  colour  industry  has  left  the  country, 
or  that  it  has  lost  ground.  The  truth  is  that  certain  parts 
of  the  industry  have  been  neglected,  whilst  others  are 
flourishing. 

The  matter  for  inquiry  is  therefore  what  part  of  the  industry 
is  here  neglected,  and  why  ? 

I  will  endeavour  to  give  answers  to  these  questions  and  show 
that  England  has  retained  just  so  much  of  the  coal-tar  industry 
as  suited  her  own  peculiar  industrial  conditions,  and  rejected 
or  neglected  the  rest  ;  that  she  resumed  the  manufacture  of 
such  portions  as,  in  the  course  of  evolution,  came  within  the 
compass  of  these  conditions  ;  that  in  this  selection  and  rejection 
the  migration  was  not  all  in  one  direction  ;  and  finally,  that 
intellectual  superiority  or  competency  on  one  side  or  the  other 
has  nothing  to  do  with  this  perfectly  natural  process  of  selection. 

If  we  compare  the  industries  which  flourish  in  England  with 
those  which  have  left,  or  are  leaving  the  country,  we  shall  have 
no  difficulty  in  arriving  at  the  criteria  by  which  to  judge  whether 
a  particular  industry  is  congenial  to  local  conditions  or  not. 
For  it  is  a  great  mistake  to  regard  the  colour  industry  as  the 
only  one  which  has  migrated  from,  or  had  been  rejected,  partially 
or  wholly,  by  England  in  the  process  of  "  selection  and 
adaptation." 

Most  prominent  among  the  factors  are  undoubtedly  the 
economic  conditions.  In  England  wages  and  salaries  are  such 
that  an  industry  which  does  not  lend  itself  readily  to  mechanical 
manipulation  and  specialisation  is,  for  that  reason,  more  or  less 
unsuitable  to  the  country.  From  this  circumstance  follow  other 
considerations,  viz.  that  there  must  be  a  sufficient  demand  for 
a  particular  article  to  warrant  an  economical  outlay  on  buildings 
and  machinery. 

What  Mr  C.  W.  Macara,  the  President  of  the  Cotton 
Spinners'  Association,  says  of  the  industry  of  Lancashire  is, 
in  substance,  true  of  every  industry  in  Great  Britain. 

He  says  :  "  The  low  cost  of  production  is  not  due  to  low 
wages  and  long  hours  of  labour  ;  wages  in  Lancashire  are  higher 


CAUSES   OF   PROGRESS   AND   RETARDATION     289 

and  hours  shorter  than  in  any  cotton-manufacturing  district  in 
the  world.  By  wages,  I  mean  what  earnings  will  command 
in  necessaries  and  comforts.  The  low  cost  of  production  is 
due  to  an  economical  first  outlay  on  buildings  and  machinery  ; 
to  highly  efficient  labour  ;  to  efficient  specialisation  in  the  various 
processes  of  the  industry.  ...  In  a  word,  it  is  due  to  enterprise, 
organisation,  and  skill." 

The  keynote  of  all  this  is  specialisation,  which  presupposes 
production  on  a  large  scale.  This  must  not  be  confounded  with  a 
large  trade,  or  a  large  aggregate  turnover.  For  instance,  on  the 
Continent  might  be  found  factories  many  times  larger  than 
corresponding  ones  in  England.  But  they  will  carry  on  a 
multiplicity  of  processes  and  produce  a  miscellany  of  articles 
which  in  England  would  constitute  several  distinct  trades. 

Not  only  do  we  have  in  England  "  combers,"  "  spinners," 
and  "weavers,"  as  separate  trades,  but  each  of  these  branches 
is  again  subdivided  according  to  quality,  some  works  confining 
themselves  to  finer  and  others  to  coarser  qualities  of  tops,  yarns, 
or  cloth.  Hence  it  is  that  though  England  is  admittedly  to  the 
fore  in  the  textile  industry,  there  are  certain  articles  which  she 
cannot  compete  in — that  is,  articles  for  which  the  demand  is 
too  restricted. 

And  that  also  is  the  chief  reason  why  certain  branches  only 
of  the  coal-tar  trade  flourish  in  England  whilst  others  are 
neglected  or  have  been  entirely  rejected.  I  say  "rejected" 
advisedly,  as  being  nearer  the  truth  than  when  it  is  alleged  that 
the  industry  has  been  "  snatched  "  from  England. 

I  will  quote  two  facts  in  support  of  this  contention.  One 
is  to  show  that  even  if  Germany  were  to  relinquish  entirely  the 
colour  trade  to-day,  England  would  not  make  a  bid  for  it,  save 
only  for  such  portions  as  suited  her  peculiar  conditions  ;  and  the 
other  is  to  show  that  such  portions  she  either  has  always  possessed 
or  is  acquiring  in  any  case. 

On  the  first  point  I  cannot  do  better  than  quote  Dr  Duisberg, 
although — to  do  him  justice — he  drew  quite  different  conclusions 
from  the  illustration. 

He  says  :  "  One  of  the  largest  colour  manufactories  in 
England  had  about  ten  years  ago  the  licence  for  exploiting  all 
the  English  patents  of  two  of  the  largest  German  colour  works, 
which  at  that  time  represented  the  value  of  many  millions  of 
marks.  It  did  not,  however,  in  any  way  avail  itself  of  this 

19 


290         THE   BRITISH   COAL-TAR   INDUSTRY 

advantage,  although  the  English  firm  had  no  restrictions  and 
were  no  worse  off  than  the  German  ones,  as  they  merely  had 
to  pay  for  this  licence  a  very  small  portion  of  their  net  profits 
to  the  patentees  for  the  working  of  the  respective  patents."  1 

In  this  case  therefore  it  could  no  longer  be  a  question  of 
inventive  faculty,  for  the  colours  were  invented,  their  processes 
worked  out,  and  at  the  disposal  of  the  English  manufacturer, 
who  yet  did  not  avail  himself  of  this  advantage.  On  the  other 
hand,  we  have — and  this  is  my  second  illustration — a  British 
Alizarin  Company  successfully  manufacturing  an  article  invented 
in  Germany !  Why  ?  The  answer  seems  obvious  enough. 
Alizarin  can  be  made  in  bulk,  whereas  "  all  the  English  patents 
of  two  of  the  largest  German  colour  works"  comprised,  on  the 
face  of  it,  a  miscellany  of  articles,  representing  "the  value  of 
many  millions  of  marks"  in  the  aggregate^  but  not  sufficient 
trade  in  any  single  article  to  make  it  into  a  specialised  and 
paying  industry  in  England. 

Phenol,  benzol,  naphthol,  naphthylamine,  their  nitro  and 
sulpho  compounds,  etc.,  are  such  articles,  and  they  are  made 
and  have  been  made  all  along  in  England,  not  only  in  sufficient 
quantity  to  supply  her  own  wants,  but  also  for  export.  Alizarin 
is  another  such  article,  and,  though  invented  in  Germany,  has 
been  successfully  manufactured  in  England  all  these  years. 

But  let  us  note  here  that  the  British  Alizarin  Company  makes 
only  those  brands  for  which  there  is  a  large  consumption  : 
alizarin  red,  alizarin  blue,  and  alizarin  orange  ;  whereas 
in  Germany  a  much  greater  variety  is  manufactured.  We  may, 
I  think,  take  it  for  granted  that  the  proportional  margin  of 
profit  on  these  three  brands  is  much  smaller  than  on  the  others 
of  lesser  consumption.  Yet  the  firm  selected  these  three  and 
rejected  the  rest. 

Thus  restricting  itself  to  what  might  be  called  the  "  bread- 
and-butter  "  articles  of  the  alizarins,  the  British  Alizarin  Company 
has,  for  the  last  seven  years,  paid  10  per  cent,  dividends  on  a 
capital  of  £138,000,  and  that  in  a  market,  be  it  remembered, 
which  is  as  open  to  the  German  makers  as  to  itself.  In  view 
of  this  should  we  be  justified  in  assuming  that  the  company  does 
not  make  the  other  brands  because  they  are  more  difficult  to 
produce,  or  because  it  has  not  the  chemists  at  its  disposal  ? 
I  believe  the  inference  that  there  is  not  sufficient  demand  for 
1  Speech  at  the  Perkin  Jubilee  banquet. 


CAUSES   OF   PROGRESS   AND   RETARDATION     291 

these  miscellaneous  brands  to  make  them  into  a  paying  industry 
to  be  nearer  the  truth. 

But — and  I  wish  you  to  note  this  point — if  a  firm  does 
not  think  it  worth  while  to  undertake  the  production  of  such 
articles  as  are  already  invented  and  at  its  disposal,  either  freely 
or  against  the  payment  of  a  percentage  on  the  net  profits  only, 
why  should  such  a  firm,  which  exists  for  profit-making,  keep 
a  staff  of  research  chemists  to  make  inventions  which  it  would 
not  know  what  to  do  with  when  made  ? 

I  imagine  the  answer  that  awaits  my  question.  Germany 
does  so,  and  makes  it  pay.  But  Germany  makes  many  other 
industries  pay  which,  under  present  conditions,  could  not  be 
profitable  in  England,  and  vice  versa. 

Again,  I  would  remind  you  that  I  am  not  contending  against 
research  work,  nor  that  this  or  that  industry  is  not  worth 
considering  because  it  does  not  lend  itself  so  readily  to  mechanical 
exploitation.  My  only  object  is  to  point  out  the  facts,  so  that 
a  remedy  might  be  sought  in  the  right  direction.  My  point 
is  that  it  is  neither  the  want  of  research  nor  shortage  of  capable 
chemists  that  is  the  reason  why  certain  branches  of  industry  do 
not  flourish  here  so  well  as  in  other  countries. 

I  will  give  an  illustration  from  my  own  experience  in  support 
of  my  contention.  Let  us  take  three  colours  that  are  produced 
on  the  fibre  : — aniline  black,  para  red,  and  naphthylamine 
Bordeaux. 

Appropriately  enough,  all  three  were  invented  in  England. 
Any  difference  there  is  in  their  production  is  in  favour  of 
Bordeaux,  which  is  certainly  the  easiest  as  well  as  the  cheapest 
to  produce,  whilst  the  black  offers  by  far  the  greatest  technical 
difficulties.  Yet,  whilst  of  aniline  black  probably  more  is 
produced  in  England  than  in  the  rest  of  Europe  put  together, 
only  comparatively  little  is  being  dyed  of  the  red,  and  scarcely 
any  of  the  Bordeaux,  though  Germany  is  doing  a  considerable 
trade  in  both  the  latter  colours. 

I  repeat  that  were  Germany  to  relinquish  the  synthetic  colour 
industry  to-day,  England  would  make  a  successful  bid  only  for 
those  portions  of  it  in  which  the  consumption  is  sufficiently  large 
to  warrant  the  laying  down  of  special  plant  and  on  an  extensive 
scale  ;  and  these  branches  she  already  possesses. 

Alizarin  and  sulphide  blacks — the  former  invented  in 
Germany  and  the  latter  in  France — both  became  British  in- 


292         THE   BRITISH   COAL-TAR   INDUSTRY 

dustries  as  soon  as  the  market  for  these  articles  was  sufficient  to 
warrant  a  profitable  outlay  for  their  manufacture.  Synthetic  indigo 
is  another  such  article  ripening  towards  eligibility  for  British 
manufacture,  and  would  be  certain  to  become  in  time  a  British 
industry,  even  without  the  recent  patent  legislation  which  impelled 
the  German  patentees  to  start  its  manufacture  in  England. 

On  the  other  hand,  the  "  two  of  the  largest  colour  works  " 
mentioned<  by  Dr  Duisberg  as  having  unsuccessfully  tried  to 
induce  an  English  colour-maker  to  exploit  their  patents  may,  now 
that  they  are  established  in  this  country,  find  out  for  themselves 
that  some  articles  can  be  more  profitably  produced  in  Germany 
than  in  England,  even  by  the  Germans  themselves. 

We  may  agree  therefore  with  Dr  Duisberg  in  his  contention 
that  it  would  not  materially  affect  England's  participation  in  the 
coal-tar  industry,  even  if  she  revised  her  patent  laws.  Not,  how- 
ever, because — as  he  seems  to  contend — the  industry  requires 
talents  which  the  nation  is  deficient  in,  but  because  the  industry 
comprises  too  many  articles  of  but  limited  consumption  to  suit 
British  conditions. 

Dr  Duisberg  is  demonstrably  wrong  in  his  classification  when 
he  assigns  to  England  industries  which  are  purely  mechanical  and 
claims  for  Germany  those  which  require  "  scientific  thought  and 
application."  His  idea  of  Englishmen  in  the  arts  is  as  hewers  of 
coal  and  minders  of  machines.  His  words  are  : — 

"  Whereas,  therefore,  the  conditions  in  England  for  many  in- 
dustries, such  as  for  the  mining  industry,  for  spinning  and  weav- 
ing, not  forgetting  inorganic  chemistry,  are  far  more  advantageous 
than  in  Germany,  the  latter  country  has  the  natural  privilege  in 
the  organic  chemical  industry." 

There  is  something  patronising  in  this  sentence — especially 
when,  in  addition  to  the  hewing  of  coal  and  minding  of  spinning 
and  weaving  machines,  he  suddenly  remembers  chemistry — 
inorganic  chemistry.  He  came  well-nigh  forgetting  it,  though  it 
represents  quite  a  respectable  turnover.  For  the  last  year  the 
exports  of  what  is  classed  under  "  Chemicals,  Drugs,  Dyes,  and 
Colours"  amounted  to  over  £16,000,000,  the  imports  to 
£10,000,000,  thus  leaving  a  balance  of  exports  over  imports  of 
about  six  million  pounds.  To  this  modest  sum,  however,  we 
would  have  to  add  the  home  consumption,  which  probably  may 
be  as  great  as  that  of  the  rest  of  Europe  put  together. 

Somehow  the  eminent  German  doctor  saw  the  "  hands  "  only 


CAUSES   OF   PROGRESS   AND   RETARDATION     293 

in  the  British  textile  mills,  and  not  the  brains  behind  them.  He 
must  have  been  so  struck  by  the  ease  with  which  these  machines 
were  worked  that  it  quite  escaped  his  notice  that  they  had  to  be 
invented,  constructed,  and  improved  until  they  became  so 
automatic  that  a  child  could  superintend  them.  Yet  those 
machines  can  teach  an  eloquent  lesson  and  illuminate  for  us  the 
very  subject  now  under  discussion.  For  it  was  necessity  which 
called  those  machines  into  being  in  a  struggle  for  existence  in  the 
strictest  sense  of  the  phrase,  and  the  secret  of  their  success  is 
specialisation  and  the  division  of  labour,  the  two  essential  and 
primary  conditions  of  British  industries. 

In  short,  the  question  whether  a  particular  industry  is  suitable 
to  English  conditions  does  not  depend  on  its  character,  whether 
it  is  mechanical  or  chemical,  organic  or  inorganic,  requiring  much 
or  little  skill,  but  merely  whether  it  is  a  bulk  industry. 

If  you  survey  the  field  you  will  find  that  in  each  case  where 
an  English  firm  takes  up  the  manufacture  of  an  article,  it  is  the 
one  with  the  lowest  margin  of  profit,  and  therefore  the  most 
difficult  to  compete  in.  What  is  it  that  makes  him  choose  thus  ? 
Not  the  smallness  of  the  profit,  nor  the  ease  or  difficulty  of  its 
production,  but  the  fact — if  I  may  use  a  slang  expression — that 
there  is  "  something  to  go  at." 

I  have  dealt  with  one  large  feature  of  the  industry  only,  and 
have  given  prominence  to  it  because,  though  obtrusively  present 
in  almost  every  important  industry  of  the  country,  it  is  entirely 
ignored  in  the  discussion  of  this  subject. 

I  do  not  pretend  that  it  is  the  only  reason  why  the  colour 
industry  of  this  country  is  not  greater  than  it  is,  but  it  certainly 
is  the  chief  one.  Nor  do  I  say  that  it  is  right  it  should  be 
so,  that  the  country  should  reject  every  industry  which  cannot 
be  harnessed  to  a  powerful  engine.  I  only  wanted  to  make 
clear  the  fact  that  the  tendency  of  British  industries  is  towards 
specialisation,  and  that,  one  by  one,  all  those  industries  which 
do  not  lend  themselves  to  this  process  are  being  neglected  or 
eliminated. 

I  could  name  scores  of  industries  which  have  left  the 
country,  or  are  in  process  of  leaving,  for  no  other  reason  ;  and 
no  amount  of  research  work  or  inventions  can  prevent  it. 
You  may  ask,  "  Is  there  no  remedy  to  arrest  this  ? "  I  believe 
there  is,  but  not  merely  by  the  erection  of  more  universities 
and  laboratories. 


294         THE   BRITISH   COAL-TAR   INDUSTRY 

You  would  have  to  devise  means  of  organising  these  lesser 
industries  in  such  a  way  that  they  could  be  exploited  profitably. 

If  a  method  could  be  found  to  do  this — and  I  do  not  think 
it  impossible  or  impracticable — the  chemists  and  inventors  would 
come  forth  without  any  special  creative  effort.  We  are  all 
worried  about  what  to  do  with  our  boys.  Create  the  field,  and 
the  workers  will  soon  crowd  around  you.  But  it  is  starting  at 
the  wrong  end  to  be  clamouring  for  the  chemists  when  you  have 
no  use  for  them. 

DISCUSSION 

Dr  CAIN  wished  to  correct  the  statement  of  Professor 
Duisberg,  which  had  been  quoted  by  Mr  Singer,  to  the  effect 
that  although  a  British  firm  of  aniline-dye  manufacturers  had 
had  the  opportunity  of  working  in  this  country  the  patents  of  two 
large  German  firms,  it  had  not  availed  itself  of  that  opportunity. 
He  thought  there  was  no  secret  as  to  the  identity  of  the  parties 
referred  to,  and  he  was  able  to  contradict  the  statement  from  his 
own  personal  knowledge,  and  to  state  that  hundreds  of  tons  of 
dyestuffs  had  been  manufactured  in  this  country  under  those 
patents  by  the  firm  mentioned. 

Mr  Singer's  attitude  with  relation  to  the  state  of  the  British 
aniline-dye  industry  was  entirely  opposed  to  that  adopted  by  the 
leading  authorities,  such  as,  for  example,  Professor  Meldola, 
Professor  Green,  and  the  late  Sir  William  Perkin.  These 
authorities  attributed  the  so-called  decline  in  the  industry  to 
the  lack  of  employment  of  research  chemists,  and  to  the  general 
want  of  education  on  the  part  of  the  manufacturers.  He  (the 
speaker)  wished  to  associate  himself  strongly  with  these  opinions. 

Mr  Singer's  contentions  were  that  there  had  been  no  decline 
in  the  industry  in  this  country,  and  if  there  had  it  was  not  due 
to  the  cause  referred  to. 

It  was  probably  true,  as  Mr  Singer  had  stated,  that  the 
manufacture  of  dyestuffs  here  had  gradually  increased,  and  in 
that  sense  the  word  "  decline  "  was  not,  perhaps,  strictly  correct, 
but  for  all  practical  purposes  it  represented  the  state  of  the 
industry  as  compared  with  that  of  Germany.  Mr  Singer  had 
shown  that  a  consideration  of  imports  and  exports  did  not 
accurately  represent  the  amounts  of  dyestuffs  manufactured, 
because  it  did  not  take  into  account  the  amount,  according  to 
Mr  Singer  a  very  large  one,  which  was  manufactured  for  home 


CAUSES   OF   PROGRESS   AND   RETARDATION     295 

consumption.  He  thought,  however,  that  no  one  would  or 
could  deny  that  roughly  about  95  per  cent,  of  the  dyes  used 
in  England  were  of  foreign  manufacture. 

That  being  so,  the  odd  few  per  cent,  could  not  represent 
very  much.  Further,  he  did  not  agree  with  the  lecturer's 
suggestion  that  British  manufacturers  would  not  bother  with 
small  manufactures,  but  would  only  take  up  the  production  of 
dyes  (or  other  materials)  which  could  be  made  all  the  year  round 
with  the  minimum  amount  of  expenditure  on  direction  and 
machinery.  Mr  Singer's  illustration  of  the  large  quantities  of 
coal-tar  products,  in  particular  the  cruder  products,  which  were 
produced  in  this  country,  was  not  a  case  where  the  British  manu- 
facturer had  selected  a  manufacture  especially  suitable  to  the 
economic  conditions  referred  to.  The  larger  quantity  of  these 
products  manufactured  here,  as  compared  with  those  furnished 
by  Germany,  particularly  in  the  past,  was  due  to  the  fact  that 
we  had  always  made  much  more  illuminating  gas  in  this  country, 
and,  broadly  speaking,  Germany  seemed  to  have  jumped,  in  the 
matter  of  illumination,  from  lamps  to  electric  light. 

There  were  dozens  of  dyestuffs,  any  one  of  which  would 
keep  a  large  works  going  continually,  but  they  had  not  been 
made  here,  or,  if  they  had,  only  to  a  small  extent.  What  was 
the  real  reason  of  this,  and  why  had  not  a  great  dyestuff  industry 
arisen  in  this  country  as  well  as  in  Germany  ?  The  cause  was, 
in  his  opinion,  the  lack  of  education  both  of  the  manufacturers 
and  of  the  people  at  large.  The  manufacturer  had  not  in  the 
past  really  understood  his  business.  He  had  not  kept  abreast 
with  scientific  discovery,  and  did  not  realise  the  possibilities 
of  such  discoveries  as  applied  to  his  manufactures  ;  consequently 
he  did  not  see  the  enormous  necessity  of  employing  research 
chemists.  What  was  true  of  the  individual  manufacturer  was 
true  also  of  the  investing  public.  The  average  investor,  he 
thought,  usually  fought  shy  of  investing  his  capital  in  businesses 
concerned  much  with  patents  or  the  possibility  of  taking  out 
patents — he  suffered  from  the  practical  mind  which  often  meant 
one  deficient  in  theoretical  knowledge.  He  was  incapable  of 
understanding  the  possibilities  of  applied  chemistry,  and  con- 
sequently capital  flowed  into  other  channels.  This  was  not, 
and  had  not  been,  the  state  of  things  in  Germany.  The  higher 
standard  of  education  in  Germany  had  had  its  effect  on  both  manu- 
facturers and  investors,  with  the  result  that  was  seen  to-day. 


296         THE   BRITISH   COAL-TAR   INDUSTRY 

Mr  SINGER,  in  reply,  said  that  his  contention  was  not  that 
England  had  as  large  a  colour  industry  as  she  might  or  should 
have,  but  that  the  reasons  given  for  this  shortcoming  were  wrong. 
The  prevalent  idea  seemed  to  be  that  England  has  lost  the  colour 
industry  for  want  of  scientific  equipment.  He  had  disproved 
this  assumption  by  showing  that  neither  has  England  lost  the 
industry,  nor  has  the  latter  retrogressed. 

The  facts  to  which  he  tried  to  give  prominence  were  :  (i) 
that  in  this  country  inventions  were  disregarded  unless  or  until 
they  related  to  objects  for  which  there  was  an  ample  market  ; 

(2)  that  failing  such  condition,  an  invention  would  be  useless, 
and    hence   an    increase  of   the  number  of   persons  engaged  in 
the  making  of  such  inventions  mere  waste  of  time  and  money  ; 

(3)  inventions  actually  made  in  this  country  were  locally  neglected, 
whilst   others,  made    abroad,  were   successfully  exploited   here. 
From  which  he  would  draw  the  inference  that  it  was  not  want 
of  education  at  all,  but  the  tending  towards  specialisation,  which 
made  mass  production  a  necessary  condition. 

He  would  put  it  to  the  test,  there  and  then,  whether  his 
reasoning  had  any  j  ustification  by  submitting  to  his  hearers  three 
proposals  which  everybody  could  answer  for  himself.  The  first 
would  be  to  form  a  company  for  the  purpose  of  employing 
research  chemists  with  a  view  of  exploiting  their  inventions. 
Would  anybody  subscribe  a  single  sovereign  to  such  a  venture 
as  a  business  speculation  ? 

His  second  proposal  would  be  to  offer  them  inventions 
already  made.  Having  assured  themselves  of  the  genuineness 
and  utility  of  the  invention,  would  not  almost  their  first  question 
be  the  probable  consumption  of  the  article,  with  a  quick  calcula- 
tion whether  it  was  at  all  worth  bothering  with  ? 

But  if — as  his  third — he  would  put  before  them  a  well- 
considered  project,  no  matter  of  what  kind,  which  showed  a 
reasonable  prospect  of  a  fair  return  of  profits,  could  it  be  con- 
ceived that  such  a  project  would  fail  for  want  of  talent,  scientific 
or  commercial  ? 

The  subject  for  inquiry  was  therefore  to  find  out  why  in- 
dustries which  could  not  be  harnessed  to  powerful  engines  are 
being  neglected,  or  by  what  means  such  industries  might  be 
organised  and  made  into  paying  concerns  consistent  with  the 
economic  and  social  conditions  of  the  country.  That  is  the 
direction  in  which  a  solution  of  the  problem  under  discussion 


CAUSES   OF   PROGRESS   AND    RETARDATION     297 

must  be  sought.  Dr  Cain  had  stated  that  he  could  mention 
dozens  of  dyestuffs  that  would  keep  a  large  works  going  con- 
tinually, but  which  had  not  been  made  here.  He  did  not  doubt 
it.  But  would  Dr  Cain  suggest  he  could  not  find  the  men  here 
to  make  them  ?  Surely  not.  Whatever  may  be  the  cause  or 
causes  of  the  neglect  of  a  particular  industry,  it  cannot  be  the 
want  of  talent,  since  that  is  always  forthcoming  in  response  to 
the  demand  for  it.  He  (the  speaker)  was  at  one  with  Dr  Cain 
in  desiring  more  education  and  more  research  work  ;  but  he 
doubted  whether  these  in  themselves  would  advance  the  colour 
industry.  He  was  rather  inclined  to  think  it  was  the  other  way 
about — that  the  expansion  of  the  colour  and  allied  industries 
would,  by  creating  a  greater  demand  for  chemists,  assist  in  their 
creation. 


XXIII. :    1914 

THE  ARTIFICIAL  COLOUR  INDUSTRY  AND 
ITS  POSITION  IN  THIS  COUNTRY 

BY  F.  M.  PERKIN,  PH.D.,  F.I.C. 

(Journal  of  the  Society  of  Dyers  and  Colourists,  loth  November  1914,  p.  339) 

THE  coal-tar  industry  was  founded  by  my  father,  and  in  the 
early  stages  of  the  work  he  received  much  encouragement  from 
Messrs  Pullar,  of  Perth,  particularly  from  the  late  Sir  Robert 
Pullar,  the  father  of  the  present  President  of  the  Society.  It  is 
doubtful  whether,  without  that  encouragement,  he  would  have 
commenced  to  manufacture  the  product  he  had  discovered. 

I  will  in  the  first  place  give  a  brief  historical  outline  of  the 
commencement  of  the  industry,  then  reasons  why  it  ultimately 
in  a  large  measure  passed  to  the  Germans,  and  finally  how  it  may 
be  possible,  in  part  at  any  rate,  to  resuscitate  the  industry.  The 
views  given  are  my  own  opinions,  but  I  give  them  for  what  they 
are  worth. 

In  the  Easter  vacation  of  1856  my  father,  who  was  at  that 
time  just  eighteen  years  of  age,  having  been  born  on  I2th  March 
1838,  found  that  when  aniline  sulphate  was  acted  upon  by 
potassium  dichromate  a  black  precipitate  was  obtained,  and  on 
examination  the  substance  was  found  to  be  "aniline  purple  or 
mauve."  This  particular  work  was  carried  out  in  a  rough 
laboratory,  which  he  had  fitted  up  in  his  father's  house,  known 
as  "  King  David's  Fort,"  at  Shadwell,  in  East  London. 

As  a  matter  of  fact,  the  actual  discovery  of  the  dye  was  an 
accident.  The  aim  which  my  father  had  in  view  was  the  syn- 
thesis of  quinine.  With  our  present  knowledge  we  know  that  it 
would  not  be  possible  to  synthesise  quinine  simply  by  the  oxida- 
tion of  aniline,  but  in  those  days,  when  organic  chemistry  was  in 

298 


THE   INDUSTRY   IN   THIS   COUNTRY        299 

its  infancy,  the  assumption  appeared  quite  probable.  In  1856 
it  seemed  quite  legitimate  to  assume  that  a  natural  product  might 
be  synthesised  if  the  elements  composing  it  could  be  brought 
together  in  the  right  proportions. 

Now,  although  the  actual  discovery  of  the  dye  was  an 
accident,  it  required  a  mind  of  particular  aptitude  to  work  up  a 
dirty  black  substance,  to  extract  the  dye,  and  afterwards  to  carry 
out  the  laborious  work  which  was  necessary  to  prove  that  it  was 
a  dye  and  could  be  used  in  place  of  dyes  obtained  from  natural 
products.  I  wish  to  lay  stress  on  this,  because  the  average 
person — the  "man  in  the  street" — is  apt  to  think  that  the  dis- 
covery of  a  substance  is  the  main  point.  It  is  really  not  the 
discovery  of  a  new  substance  which  is  the  chief  thing,  for 
thousands  of  substances  have  been  discovered  which  have  been 
put  on  one  side  as  useless  until  the  inventive  mind  came  along 
and  opened  out  new  branches  of  industry. 

My  father,  having  discovered  this  unprepossessing  black 
material,  instead  of  throwing  it  away,  experimented  and  found  that 
a  brilliant  colouring  matter  could  be  produced  from  it  which  had 
the  properties  of  a  dye,  and  which  resisted  the  action  of  light 
remarkably  well.  Samples  of  silk  and  cotton  were  dyed  with  it 
and  sent  to  Messrs  Pullar,  of  Perth,  who,  after  examining  them, 
wrote  on  I2th  June  1856  : — 

"  If  your  discovery  does  not  make  the  goods  too  expensive,  it 
is  decidedly  one  of  the  most  valuable  that  has  come  out  for  a  long 
time.  This  colour  is  one  that  is  wanted  in  all  classes  of  goods, 
and  could  not  be  obtained  fast  on  silks,  and  only  at  great  expense 
on  cotton  yarns  ....  and  does  not  stand  the  tests  that  yours 
does,  and  fades  by  exposure  to  air." 

After  further  experiments,  a  patent  was  taken  out  (No.  1984, 
1856),  and  it  was  decided  to  commence  manufacturing.  In  June 
1857  the  building  of  the  works  was  begun.  In  December  of 
the  same  year,  the  technical  difficulties  of  manufacturing  nitro- 
benzene from  benzene  having  been  overcome,  also  the  manu- 
facture of  aniline  on  a  large  scale  from  nitrobenzene,  and  finally 
the  oxidation  and  preparation  of  the  dye,  aniline  purple,  or 
Tyrian  purple  as  it  was  then  called,  was  put  on  the  market  and 
used  for  silk  dyeing  in  the  dyehouse  of  Mr  Thos.  Keith,  of 
Bethnal  Green. 

In  introducing  the  new  colour,  an  enormous  amount  of  experi- 
mental work  had  to  be  carried  out.  Mordants  for  use  in  cotton 


300         THE   BRITISH    COAL-TAR   INDUSTRY 

printing  had  to  be  devised.  Many  experiments  were  necessary 
before  satisfactory  results  were  obtained  in  dyeing  wool  and 
silk  with  this  new  dye.  It  was,  in  fact,  all  pioneering  work 
from  purifying  the  raw  material  and  devising  new  plant,  to  finally 
applying  the  new  product. 

In  connection  with  the  raw  product — benzol — it  is  interesting 
to  note  that  it  was  manufactured  only  in  small  quantities  in  1856, 
and  that  the  price  was  55.  per  gallon  for  a  comparatively  crude 
product,  which  had  to  be  distilled  before  it  could  be  used.  The 
coal  tar  itself  was  a  drug  on  the  market,  and  a  great  nuisance  to 
the  gas  manufacturer.  With  the  advent  of  the  aniline  dyes, 
and  the  consequent  call  for  more  and  more  of  the  products 
contained  in  the  tar,  the  conditions  changed  and  by  degrees  tar- 
distilling  plants  were  erected,  and  became  a  source  of  profit  to 
the  gas  manufacturer. 

The  introduction  of  a  new  colour  from  a  novel  source 
naturally  attracted  a  great  deal  of  attention,  and  as  a  consequence 
many  workers  came  into  the  field  and  a  large  amount  of  research 
work  was  carried  out  with  aniline  and  allied  products,  and  the 
number  of  synthetic  dyes  gradually  increased.  The  second 
aniline  dye,  magenta  or  fuchsine,  was  discovered  in  France  by 
Verguin,  in  1859,  who  produced  it  by  heating  commercial  aniline 
with  tin  tetrachloride.  In  these  early  days  quite  a  number  of 
British  patents  were  taken  out,  although  of  course  a  great  deal 
of  work  was  being  carried  on  on  the  Continent.  It  must  also  not 
be  forgotten  that  a  large  amount  of  pioneering  work  was  instituted 
under  the  direction  of  the  German  chemist,  Professor  Hofmann, 
at  the  Royal  College  of  Chemistry,  London.  In  fact,  the  in- 
fluence of  Hofmann  was  of  enormous  value,  as  he  imbued  his 
students  with  a  love  of  research,  and  taught  them  the  importance 
of  thoroughness  in  their  work.  The  Germans,  recognising 
Hofmann's  great  gifts,  ultimately  induced  him  to  return  to  his 
native  land  as  a  Professor  at  Berlin  University. 

In  the  early  days  of  the  aniline-dye  industry,  probably 
owing  mainly  to  the  influence  of  Hofmann,  there  were  many 
German  chemists  in  English  works,  a  number  of  whom  returned 
to  Germany  and  have  most  materially  helped  the  German  colour 
industry. 

My  father's  works  at  Greenford  Green  in  Middlesex  were 
the  first  coal-tar  colour  works,  but  quite  a  number  of  other  works 
sprang  up  within  a  few  years.  Some  of  these  no  longer  exist, 


THE   INDUSTRY   IN   THIS   COUNTRY         301 

but  others  are  still  with  us  and  are  of  considerable  size,  employ- 
ing a  large  number  of  hands. 

A  short  time  after  the  Greenford  Works  had  been  founded, 
Messrs  Simpson,  Maule  &  Nicholson  commenced  to  manu- 
facture dyes,  Edward  Chambers  Nicholson,  one  of  the  partners 
and  a  student  of  Hofmann's,  being  a  chemist  of  high  attainments. 
Simpson,  Maule  &  Nicholson  were  originally  manufacturers 
of  fine  chemicals.  When  mauve  was  produced,  they  took  up 
the  manufacture  of  nitrobenzene  and  then  aniline,  and  gradually 
developed  into  manufacturers  of  dyes,  being  the  first,  1  believe, 
to  manufacture  rosaniline  in  this  country,  and  producing  it  in  a 
high  state  of  purity. 

Messrs  Roberts,  Dale  &  Co.  began  working  before  1860. 
Levinstein's  commenced  in  a  small  way  in  1864.  Read  Holliday 
&  Sons,  Williams  Bros.,  and  Dan  Dawson  all  commenced  about 
1865.  From  the  first  all  these  firms  employed  highly  trained 
chemists  who,  by  their  research  work,  did  much  to  place  the 
industry  on  a  strong  basis.  Many  of  the  chemists,  however, 
were  Germans  who,  as  already  mentioned,  ultimately  returned  to 
the  land  of  their  birth  and,  for  reasons  which  will  be  mentioned 
later,  it  was  not  possible  to  replace  them  by  men  of  equal  calibre. 
The  names  of  a  few  of  these  German  chemists,  who  did  so  much 
valuable  work  in  England,  may  be  mentioned  : — Dr  Caro,  who 
ultimately  became  chief  chemist  to  the  Badische  Anilin-  und  Soda- 
Fabrik  ;  Dr  Martius,  who  was  later  appointed  chief  chemist  to 
the  Berlin  Actiengesellschaft ;  Peter  Griess,  the  discoverer  of  the 
diazo  reaction  (chemist  to  Allsopp's  Brewery  at  Burton-on- 
Trent)  ;  and  Dr  Otto  N.  Witt,  who  became  Professor  of 
Chemistry  at  the  Charlottenburg  Technische  Hochschule. 

Up  to  1875  *ne  British  industry  was  in  a  flourishing  con- 
dition, and  fairly  held  its  own  against  foreign  competition  ;  and 
a  very  large  number  of  important  patents  were  taken  out  in 
this  country.  For  example,  Dr  David  Price,  in  1859,  patented 
violine,  purpurine,  and  roseine,  which  he  obtained  by  oxidation 
of  aniline  with  lead  peroxide.  Medlock  took  out  a  patent  in 
1860  for  magenta.  In  the  same  year,  Greville  Williams  dis- 
covered quinoline  blue,  afterwards  known  as  cyanin.  Patents 
for  violets  were  taken  out  in  1860  by  Dale  and  Caro,  and  by 
Smith  and  Coleman.  In  1862  Perkin  patented  another  series 
of  violets,  and  in  1863  Hofmann  discovered  a  violet  known  as 
Hofmann's  violet,  which  was  manufactured  by  Simpson,  Maule 


302         THE   BRITISH   COAL-TAR   INDUSTRY 

&  Nicholson.  Aniline  black,  probably  the  fastest  of  all  blacks, 
was  discovered  by  Lightfoot  in  1 863.  It  is  unnecessary  to  further 
enumerate. 

A  very  great  stride  in  organic  synthesis  was  made  in  1867  by 
the  German  chemists,  Graebe  and  Liebermann,  who  showed  that 
the  vegetable  dye,  alizarin,  could  be  prepared  by  fusing  dibromo- 
anthraquinone  with  caustic  potash.  They  patented  this  process, 
but  it  was  far  too  expensive  to  be  of  commercial  importance. 

My  father,  when  with  Hofmann,  having  had  special  experience 
of  anthracene,  and  having  kept  considerable  quantities  from  the 
time  when  he  was  a  student,  was  naturally  much  interested  that 
anthraquinone,  which  is  obtained  from  anthracene,  could  be 
converted  into  alizarin.  He  therefore  studied  the  matter 
further,  and  found  that  alizarin  could  be  produced  by  sul- 
phonating  anthraquinone  with  fuming  sulphuric  acid  and  then 
fusing  with  caustic  soda.  He  also  devised  another  method  which 
consisted  in  chlorinating  anthracene  and  then  treating  with 
sulphuric  acid  and  afterwards  with  caustic  soda.  On  treating  the 
melt  obtained  by  one  or  other  of  these  methods  with  acid,  a 
yellow  precipitate  was  obtained,  which  dyed  madder  mordants 
with  the  greatest  ease. 

All  the  alizarin  used  had,  up  to  this  time  (1869),  been  pro- 
duced from  the  root  of  the  madder  plant.  This  then  was  the 
first  synthesis  of  a  natural  or  vegetable  colouring  matter. 

At  the  same  time  that  experiments  were  being  carried  out 
in  England,  the  German  chemists,  Caro,  Graebe,  and  Liebermann, 
were  also  investigating  the  subject,  and  discovered  the  sulphona- 
tion  process  about  the  same  time  as  Perkin.  Although  the 
patents  were  filed  within  a  day  of  each  other,  artificial  or  synthetic 
alizarin  was  first  manufactured  in  this  country,  and  until  1874 
the  Germans  sent  very  little  into  the  United  Kingdom. 

In  1868  the  amount  of  madder  root  produced  was  estimated 
at  70,000  tons  a  year,  but  in  a  few  years  the  artificial  product 
almost  completely  replaced  the  natural  colour,  and  madder 
ceased  to  be  grown.  The  total  output  of  alizarin  from  the 
madder  root  was  about  750  tons  in  1868,  but  in  1912  the  out- 
put of  the  synthetic  product  had  risen  to  about  2000  tons,  four- 
fifths  of  which  was  manufactured  in  Germany. 

The  development  of  this  branch  of  the  coal-tar  colour 
industry  was  thus  described  by  my  father  in  his  Hofmann 
Memorial  Lecture  in  1896  : — 


THE   INDUSTRY   IN   THIS   COUNTRY 


303 


"Before  the  end  of  the  year  1869  we  had  produced  i  ton 
of  this  colouring  matter  in  the  form  of  paste  ;  in  1870,  40  tons  ; 
in  1871,  220  tons;  and  so  on  in  increasing  quantities  year  by 
year.  As  we  had  been  successful  in  producing  artificial  alizarin, 
others  did  not  run  much  risk  in  following  our  lead  ;  yet  up  to 
the  end  of  1870  the  Greenford  Green  works  were  the  only  ones 
producing  artificial  alizarin.  German  manufacturers  then  began 
to  make  it,  first  in  small  and  then  in  increasing  quantities,  but 
until  the  end  of  1873  there  was  scarcely  any  competition  with 
our  colouring  matter  in  this  country." 

He  then  went  on  to  say — and  the  remarks  were  not  only 
directed  to  his  own  work  but  to  the  work  of  other  firms,  notably 
Simpson,  Maule  &  Nicholson,  who  for  some  years  were  the 
largest  coal-tar  colour  producers  in  the  world  : — 

"  From  the  foregoing  it  is  seen  that,  as  in  the  case  of  the 
aniline  colours,  all  the  pioneering  work  connected  with  the 
foundation  and  establishment  of  this  branch  of  the  coal-tar 
colour  industry  was  also  done  in  this  country. 

"  For  the  due  development  of  this  industry,  it  was  necessary 
not  only  to  attend  to  technical  processes,  but  also  to  carry  on 
scientific  research  in  connection  with  it." 

The  neglect  of  scientific  research  during  the  next  decade  was  the 
reason  why  the  coal-tar  colour  trade  ^  established  as  it  was  in  this 
country^  gradually  got  forced  out  by  German  competition. 

In  1874  the  Greenford  Works  were  sold  to  Messrs  Brooke, 
Simpson  &  Spiller,  the  manufacture  of  alizarin  being  taken 
over  at  a  later  date  by  the  British  Alizarin  Company. 

I  have  seen  it  in  the  Press,  and  have  also  heard  it  in  con- 
versation, that  it  was  not  a  very  patriotic  step  to  dispose  of  a 
successful  works  at  the  early  age  of  thirty-six.  The  reasons  for 
doing  so  were  practically  these.  My  father  and  his  brother  had 
had  a  very  difficult  fight  to  establish  the  works,  and  had  at  last 
reaped  some  benefit  from  their  struggle.  The  use  of  aniline 
and  alizarin  dyes  was  increasing  by  leaps  and  bounds,  and 
their  agents  all  over  the  country  were  urging  them  to  increase 
their  output  largely.  This  practically  meant  doubling  the  size 
of  the  works  ;  and  this  again  meant  that  they  would  have  to 
sink  most  of  the  capital  which  they  had  made,  in  bricks,  mortar, 
and  machinery.  Although  my  father  preferred  a  quiet  life  in 
which  to  devote  himself  to  research  work,  the  increasing  of  the 
works  would  probably  not  have  been  an  insuperable  difficulty  or 


3o4         THE   BRITISH   COAL-TAR   INDUSTRY 

prevented  him  from  carrying  on  the  business  ;  but  the  necessity 
of  having  more  trained  research  chemists,  if  the  works  were  to 
be  carried  on  satisfactorily,  became  increasingly  apparent.  It 
was  not  possible  for  one  brain,  however  energetic  and  fertile,  to 
carry  out  all  the  necessary  research  required  in  a  large  works. 
Research  chemists,  however,  could  not  be  obtained.  Our 
universities  did  not  train  them.  True,  Germans  could  be  had 
at  moderate  salaries  ;  but  German  research  chemists,  after  they 
had  obtained  a  thorough  knowledge  of  the  processes,  had  a 
tendency  to  go  back  to  their  own  country,  where  they  were 
received  with  open  arms  and  offered  high  salaries  by  the  German 
companies. 

In  an  industry  such  as  that  of  the  aniline  dyes,  continual 
change  is  necessary.  Consequently,  a  number  of  highly  trained 
research  chemists  must  be  employed,  and  it  is  the  works  which 
can  turn  out  the  largest  number  of  new  colours,  and  at  the  same 
time  improve  the  methods  of  manufacture  and  the  quality  of  the 
older  ones,  which  will  obtain  the  market. 

This  is  what  the  Germans  have  done.  It  is  not  correct  to 
say — except  to  a  limited  extent — that  they  have  stolen  the 
artificial  colour  industry  from  us.  There  certainly  has  been  a 
lot  of  piracy.  In  the  early  days  of  the  industry,  German  patent 
laws  were,  to  say  the  least  of  it,  chaotic,  each  State  either  having 
its  own  laws  or  its  own  ideas  as  to  the  administration  of  the 
patent  laws.  Therefore,  for  all  practical  purposes,  no  patent  law 
existed.  It  followed,  consequently,  that  the  Germans  had  the 
brains  of  the  world  at  their  disposal  and  they  had  to  pay  no  fees 
for  their  use.  The  moment  a  patent  was  published  it  was  seized 
upon  by  the  German  firms.  If  a  process  was  worked  secretly, 
the  Germans,  either  by  research  work  or  by  other  means,  dis- 
covered it  and  appropriated  it.  The  products  manufactured  by 
them  were  sent  into  this  country  ;  it  was  vain  to  prosecute  their 
agents,  because  when  the  Germans  found  this  was  being  done 
they  supplied  the  goods  direct  to  the  consumers.  They  sent 
their  travellers,  many  of  them  skilled  chemists,  all  over  the  world. 
They  were  therefore  able  to  show  how  the  dyes  were  best 
employed.  The  British  manufacturers  were,  as  a  rule,  content 
with  issuing  circulars  to  their  customers,  warning  them  not  to 
use  inferior  foreign  goods.  As  a  matter  of  fact,  the  goods,  as  a 
rule,  were  not  inferior  to  the  British,  and  were  often  cheaper. 
It  is,  however,  an  undoubted  fact  that  the  German  colour  works, 


THE   INDUSTRY   IN   THIS   COUNTRY         305 

when  they  were  first  founded,  stole  the  work  of  English  brains. 
The  British  Government  protected  their  processes  by  allowing 
them  to  take  out  patents  in  this  country  which  they  were  not 
required  to  work.  On  the  other  hand,  German  patents  were 
refused  to  the  British  inventors.  This  was  the  case  with  the 
alizarin  patents  ;  they  were  granted  to  Germans  in  England,  but 
refused  to  Englishmen  in  Germany. 

I  do  not  think  that  the  German  competition  with  alizarin 
was  very  serious  until  after  1874,  because,  up  to  that  time,  it 
could  be  manufactured  and  sold  at  a  good  profit  at  a  price  which 
did  not  admit  of  much  German  undercutting.  Shortly  afterwards 
the  price  of  the  alizarin  paste  in  this  country  was  raised,  and 
this  gave  the  Germans  their  chance,  which  they  seized  with 
characteristic  energy  and  undersold  the  English  manufacturers. 
The  English  policy  should,  of  course,  have  been  in  the  opposite 
direction,  to  keep  the  price  low,  particularly  as  the  Germans  were 
getting  in  a  position  to  supply  the  whole  demand,  if  they  could 
only  obtain  the  trade.  As  a  matter  of  fact,  by  combining  together, 
the  German  manufacturers  for  a  time  practically  killed  the 
British  alizarin  industry,  and  had  it  not  been  for  the  Turkey 
Red  Dyers'  Association,  who  combined  to  manufacture  alizarin, 
the  trade  would  probably  have  entirely  left  the  country.  At  any 
rate,  the  Germans  have  made  very  great  profits,  and  employed 
these  in  the  first  case  to  write  off  their  capital  expenditure,  and 
secondly  to  reconstruct  and  equip  their  works  with  magnificent 
laboratories,  staffed  with  skilled  research  chemists.  The  patent 
laws,  until  the  Bill  of  1907  was  passed,  allowed  foreign  nations 
to  patent  any  process  in  this  country  simply  to  prevent  us  manu- 
facturing, while  we,  if  we  patented  abroad,  must  manufacture  the 
product  in  the  particular  country  in  which  the  patent  was  taken 
out  within  a  reasonable  period,  or  else  grant  a  licence. 

In  1907  the  Patent  Laws  Amendment  Act  was  passed,  in 
which  it  was  made  compulsory  for  a  foreign  patentee  either  to 
work  his  patent  in  this  country,  or  else  to  be  compelled  to  grant 
a  licence.  Unfortunately,  many  loopholes  for  evading  this  Act 
have  been  discovered,  and  it  has  not  been  so  successful  as  was 
anticipated. 

With  our  own  patent  laws  against  us,  the  Germans  made  the 
most  of  it.  But  the  German  spy  system,  of  which  we  have  seen 
so  much  recently,  was  also  against  us.  In  many  cases,  however, 
our  want  of  business  method  and  always  our  disdain  of  research 

20 


306         THE   BRITISH   COAL-TAR   INDUSTRY 

work  were  against  us.  After  a  process  was  once  started  it  was, 
and  even  to-day  is,  largely  worked  by  rule  of  thumb.  I  grant 
you  there  is  a  stirring  amongst  the  dry  bones,  yes,  a  great  stirring, 
but  if  we  are  going  to  take  our  place  in  the  manufacture  of 
aniline  dyes  and  fine  chemicals,  the  stirring  will  require  to  be 
very  much  more  vigorous,  and  unless,  after  being  stirred,  the 
bones  are  going  to  be  jointed  together,  little  ultimate  good  will 
result. 

I  have  pointed  out  how  the  Germans,  owing  to  our  patent 
laws,  were  able  to  make  use  of  our  brains,  and  one  cannot  help 
thinking  how  fertile  those  brains  were  with  new  ideas,  and  with 
initiative  to  carry  out  the  ideas  from  the  experimental  to  the 
manufacturing  stage.  It  must  be  remembered,  however,  that  the 
number  of  these  pioneers  was  not  very  great,  and  it  is  small 
wonder  if,  when  they  found  their  ideas  being  exploited  by  others, 
they  were  inclined  to  lose  interest,  and  retire  from  the  fray. 
Whether  or  not  this  was  the  case  I  am  unable  to  say,  but  in  this 
particular  line  of  industry  we  seemed  to  lose  our  pioneering 
interest.  The  existing  works  in  some  cases,  at  any  rate,  began 
to  live  on  their  past  reputation  and  seemed  to  make  very  little 
effort  to  compete  with  their  German  rivals.  On  the  business 
side  they  did  not  take  sufficient  trouble  to  keep  their  customers 
or  to  open  out  new  markets.  The  dyer  was  told,  if  not  in  words, 
at  any  rate  by  action  or  want  of  action,  "  These  colours  have 
always  been  admired  and  have  been  manufactured  by  us  for  years, 
we  don't  see  any  reason  for  altering  the  shades  or  the  methods 
of  dyeing." 

In  the  meantime,  however,  the  Germans  were  flooding  the 
markets  with  new  dyes  and  new  shades  and  sending  round  their 
travellers  by  the  score.  These  travellers  were  not  simply  sales- 
men, but  in  many  cases  trained  chemists,  who  were  prepared  to 
go  into  the  dyehouse  and  show  the  dyer  how  to  apply  the  dyes. 

The  question  of  capital  also  had  a  great  deal  to  do  with  the 
advancement  of  the  artificial  colour  industry  abroad.  In  this 
country  all  the  firms  were  privately  owned,  being  more  or  less 
family  concerns.  To-day  this  is  in  the  main  still  the  case.  In 
Germany  it  was  and  is  otherwise.  They  are  big  commercial 
concerns,  supported  by  outside  capital  and  also  by  the  banks. 
Furthermore,  a  large  slice  of  the  profits  has  always  been  put  by 
for  developing  the  works,  for  new  machinery,  and  for  research 
work.  We  in  this  country  have  been  too  prone  to  take  too 


THE   INDUSTRY   IN   THIS   COUNTRY         307 

much  out  of  the  business,  instead  of  building  up  large  reserves. 
One  might  say,  why  then  was  not  outside  capital  brought  in  to 
increase  the  size  and  output  of  the  works  ?  The  reason  probably 
was  this — that  capital  found  a  more  remunerative  opening  in 
shipping  industries  and  the  building  of  docks,  the  opening  up 
of  coal  mines,  in  the  heavy  chemical  trade,  and  in  engineering 
concerns,  etc.  Also  a  large  amount  of  capital  was  invested 
abroad  to  finance  British  or  foreign  undertakings  from  which 
good  profits  could  be  obtained. 

One  of  the  chief  causes  of  our  not  being  able  to  hold  the 
artificial  colour  industry  which  had  been  founded  in  this  country, 
and  the  real  cause  of  the  German  pre-eminence,  and  for  which 
they  deserve  every  honour,  was  the  lack  of  industrial  research. 
One  of  the  reasons  why  so  many  of  the  students  of  Hofmann 
rose  to  such  eminence  was  the  love  of  research  with  which  he 
imbued  them.  To-day  our  manufacturers  are  awakening  to  the 
need  and  value  of  research,  but  for  many  years,  although  a 
chemist  was  attached  to  most  of  the  works,  he  had  in  the  main 
simply  routine  work  to  pursue,  which  either  gave  him  no  time 
or  incapacitated  him  for  research,  and  this  is  still  largely  the  case. 
Small  wonder  is  it  that  our  manufacturers  were  unable  to  compete 
with  the  Germans.  In  the  German  works,  shortly  after  their 
foundation,  magnificent  laboratories  with  all  the  latest  scientific 
apparatus  were  erected.  Libraries  stocked  with  the  latest  literature 
were  installed — everything  was  there  which  might  be  required  for 
the  investigations  in  hand. 

Having  made  these  preparations,  chemists  were  employed 
who  had  had  a  thorough  training.  Before  they  could  take  their 
degrees  it  was  compulsory  that  they  should  carry  out  an  original 
investigation  along  some  line  of  research.  The  engineers  employed 
were  also  highly  trained  men  with  a  good  chemical  knowledge, 
many  of  them  having  received  a  university  education.  In  the 
works  the  chemist  and  engineer  worked  hand  in  hand.  Thus, 
when  the  chemist  had  discovered  some  new  material  or  process 
in  the  laboratory,  it  was  further  worked  out  in  collaboration  with 
the  engineer-chemist.  The  product  first  produced  in  the  laboratory 
was  next  made  on  a  semi-commercial  scale,  and  if  this  proved 
successful,  the  commercial  plant  was  erected  and  the  material 
manufactured  in  bulk. 

As  the  output  of  the  works  increased,  so  the  number  of 
chemists  taken  into  the  works  increased  until,  as  is  well  known, 


3o8         THE   BRITISH   COAL-TAR   INDUSTRY 

some  works,  such  as  the  Badische,  and  Meister,  Lucius  &  Brun- 
ing,  employ  over  two  hundred  research  chemists.  The  fact  is  that 
almost  the  whole  of  the  technical  staff  are  more  highly  trained  than 
is  usually  the  case  here.  There  is  also  in  Germany  a  much  closer 
relationship  between  the  professors  of  chemistry  in  the  universities 
and  polytechnic  institutes  and  the  manufacturers.  This  is  good 
for  the  professors  and  good  for  the  manufacturers,  as  it  reacts 
upon  the  training  of  the  student. 

How  could  British  manufacturers  who,  if  they  did  not  scorn 
research  did  not  recognise  its  value,  compete  under  these  con- 
ditions ?  During  the  last  decade  British  colour  makers  have 
been  holding  their  own  in  certain  lines,  and  even  improving  their 
position,  owing  to  the  fact  that  they  have  been  increasing  their 
technical  staff.  But  they  have  been,  and  are,  severely  handi- 
capped by  the  enormous  German  advances  and  by  the  great 
variety  of  products  the  Germans  have  been  able  to  supply  to 
the  consumers.  The  agent  of  a  German  firm  can  go  to  the  dyer 
and  offer  him  all  the  shades  he  requires,  the  British  manufacturer 
can  only  supply  a  few  :  consequently,  the  German  gets  the  order 
— it  saves  so  much  trouble. 

There  are  other  reasons  which  are  more  closely  related  to  the 
German  business  methods,  but  I  will  not  go  into  these,  as  I  do 
not  wish  to  enter  into  controversial  matters. 

I  am  not  fond  of  the  expression,  "  War  on  German  Trade." 
Is  it  not  better  to  say,  "  Opportunity  for  British  Trade  and  the 
Capture  of  New  Markets  "  ?  The  Germans  thoroughly  deserve 
the  pre-eminent  position  which  they  have  attained  in  the  artificial 
colour  industry.  It  is  in  the  main  due  to  painstaking  research, 
backed  by  thorough  business  organisation.  Some  of  their 
business  methods,  it  is  true,  are  such  that  we  should  not  care 
to  see  them  copied  here,  but  the  main  reason  has  been  the  lack 
of  research,  and  of  making  opportunities,  instead  of  waiting  for 
them  to  come. 

Did  not  the  Germans  deserve  to  capture  the  indigo  industry  ? 
The  research  on  this  subject  was  carried  out  on  a  truly  colossal 
scale.  Many  chemists  were  engaged  for  a  period  of  over  twenty 
years  upon  research  work  in  order  to  produce  this  product  syn- 
thetically on  a  commercial  scale  at  a  price  which  would  compete 
with,  and  even  undersell,  the  natural  product.  It  is  stated  that 
before  a  single  pound  of  synthetic  indigo  was  placed  on  the 
market  over  £  1,000,000  had  been  spent  during  the  twenty  years. 


THE   INDUSTRY   IN   THIS   COUNTRY        309 

The  literature,  patent  and  otherwise,  upon  the  subject  is  one  of 
the  finest  chapters  in  the  history  of  chemical  technological  re- 
search. It  is  not  my  intention  to  enter  into  the  details  of  this 
magnificent  work — time  will  not  permit,  and  most  of  you  are 
familiar  with  it.  Had  the  indigo  planters  not  been  so  sure  of 
their  position,  they  would — when  the  first  discovery  of  synthetic 
indigo  was  announced  in  1878 — have  carried  out  experiments  to 
see  if  they  could  not  improve  the  quality  and  quantity  of  their 
product,  but  they  sat  by  with  folded  hands.  When  it  was  too 
late  they  cried  out  that  the  introduction  of  synthetic  indigo  was 
a  bolt  from  the  blue.  They  should  have  watched  the  signs,  in 
which  case  they  would  not  have  been  so  surprised  ;  aye,  they 
might  even  have  arrested  or  retarded  the  falling  of  the  bolt. 

I  have  given  some  of  the  chief  reasons  why  the  artificial  colour 
industry  was  lost  to  this  country.  There  is,  however,  another 
one.  In  the  preparation  and  purification  of  some  of  the  dyes,  it 
is  necessary  to  employ  large  quantities  of  pure  alcohol.  The 
enormous  cost  of  pure  alcohol  in  this  country,  compared  to  its 
cost  in  Germany,  owing  to  Government  duty  and  excise  re- 
strictions, has  made  its  use  on  a  large  scale  prohibitive,  and  has 
most  certainly  been  a  contributory  cause  in  helping  the  German 
manufacturers.  Within  the  last  few  years  these  restrictions 
have  been  considerably  mitigated — largely  owing  to  the  per- 
severing efforts  of  Mr  Thomas  Tyrer.  Unfortunately,  much  yet 
remains  to  be  done.  Although  Government  has  given  relief, 
the  officials  who  have  to  administer  the  Government  Acts  seem 
to  forget  they  are  public  servants,  placed  there  for  the  good  of 
the  country.  Several  manufacturers  to  my  knowledge,  after 
inquiring  into  the  matter,  found  the  use  of  alcohol  so  hedged 
and  bound  about  with  red  tape  and  officialism,  that  they  were 
unable  to  take  advantage  of  the  Act.  In  the  fine  chemical  trade, 
that  is  the  manufacture  of  drugs  and  photographic  chemicals, 
the  use  of  pure  alcohol  is  of  even  greater  importance  than  in  the 
colour  industry.  The  fine  chemical  trade  in  synthetic  drugs  and 
photographic  chemicals  never  has  been  a  British  industry.  It  is 
entirely  due  to  German  research  work,  and  we  have  never  tried 
to  develop  it  here.  It  is,  however,  a  very  important  industry, 
and  there  is  no  reason  why  it  should  not  now  be  developed,  at 
any  rate  in  a  partial  state,  in  this  country.  Alcohol,  however,  is 
a  very  important  reagent  for  this  industry.  British  manufacturers 
can  produce  good  cheap  alcohol,  if  there  is  a  demand  for  it ;  but 


310 


THE   BRITISH   COAL-TAR  INDUSTRY 


while  its  use  is  hedged  with  difficulties,  those  who  use  it  will 
employ  it  in  minimum  quantities  only.  Like  most  commodities, 
it  can  be  made  more  cheaply  in  large  than  in  small  quantities. 

Let  me  now  briefly  summarise  the  causes  which  have  led  or 
contributed  to  the  present  position  of  the  artificial  colour  industry 
in  this  country  : 

(1)  The  character  of  the  British  patent  laws  and  the  want  of 

patent  laws  in  Germany,  whereby  the  Germans  were 
able  to  exploit  our  brains. 

(2)  Slackness  on  the  part  of  the  early  British  manufacturers 

(after  a  certain  period  of  prosperity). 

(3)  Industrial  chemical  research    carried  out  in    Germany,  but 

neglected  by  us. 

(4)  German  business  organisation. 

(5)  Restrictions  on  the  use  of  alcohol. 

That  the  artificial  colour  industry  is  in  a  bad  position  is  self- 
evident.  A  devastating  war  has  broken  out,  stopping  our  supply 
of  imported  colours,  and  what  is  the  result  ?  There  is  a  dye 
famine.  Dyers  cannot  carry  out  their  contracts  because,  although 
willing  to  pay  almost  any  price,  they  cannot  obtain  the  dyes.  It 
must  be  remembered  also  that  aniline  dyes  are  used  for  a  great 
many  purposes  other  than  that  of  dyeing  textiles.  Paper,  leather, 
bones,  feathers,  straw,  grasses,  etc.,  are  all  dyed  with  aniline  dyes. 
They  are  employed  for  dyeing  wood,  particularly  in  the  furniture 
trade.  Very  large  quantities  are  used  in  paints  in  the  form  of 
lakes.  Even  in  confectionary  they  are  employed.  All  these 
industries  are  hit. 

So  dependent,  indeed,  are  our  manufacturers  upon  dyes,  that 
the  stoppage  of  the  supply  is  beginning  to  cause  great  distress 
amongst  thousands  of  our  workers,  and  this  distress  will  increase 
as  the  available  supplies  are  used  up.  Colonel  H.  A.  Foster 
recently  pointed  out,  before  the  Bradford  Chamber  of  Commerce, 
that  although  the  value  of  the  dyes  imported  might  not  exceed 
£2,000,000  to  £3,000,000  per  annum,  yet  taking  textiles  alone 
it  involves  indirectly  a  turn-over  of  about  .£100,000,000.  If  we 
take  into  account  some  of  the  other  uses  which  I  have  mentioned, 
this  enormous  sum  must  be  greatly  exceeded. 

The  British  colour  makers  are  increasing  their  output,  but 
since  before  the  war  they  were  supplying  only  about  1 5  per  cent. 
of  the  amount  used  in  the  United  Kingdom,  it  is  obvious  that 


THE   INDUSTRY   IN   THIS   COUNTRY         311 

they  will  not  be  in  a  position  for  a  long  time  to  meet  the  demand. 
Furthermore,  the  Germans  manufactured  very  large  quantities  of 
dyes  which  have  never  been  made  here. 

What,  then,  is  to  be  done  ?  I  notice  that  the  Bradford 
Chamber  of  Commerce  unanimously  passed  a  resolution  on 
2 yth  October  "urging  upon  His  Majesty's  Government  the 
vital  necessity  for  immediately  adopting  measures  for  furnishing 
such  support  as  is  essential  to  the  establishing  and  effectual  con- 
tinuance of  the  manufacture  of  aniline  dyes  upon  an  adequate 
scale  in  this  country." 

To  my  mind,  the  most  important  part  of  the  resolution  is 
contained  in  the  words  "  and  effectual  continuance  of  the  manu- 
facture of  aniline  dyes."  If  the  industry  is  founded,  it  is  the 
bounden  duty  of  the  Government  to  see  that  it  is  not  stifled 
again  at  the  end  of  the  war. 

Capitalists  who  might  be  willing  to  risk  their  money  in  putting 
up  colour  works  say  :  But  what  is  to  happen  after  the  war  ? 
The  Germans  will  again  flood  the  market  and  undercut.  In  all 
probability  they  have  accumulated  supplies  and  will  be  willing  to 
get  rid  of  them  at  almost  any  price.  Will  the  Government 
guarantee  that  for  a  certain  number  of  years  all  dyeing  which  is 
done  for  Government  Departments  shall  be  dyed  only  with 
British-made  dyes  ?  If  the  Government  agree,  and  the  manu- 
facturers and  users  of  this  country  should  compel  them  to  agree, 
what  about  other  than  Government  users  ?  Will  they  rush  back 
to  buy  in  the  cheapest  market,  because  it  goes  without  saying 
that  in  most  cases,  for  some  time  at  least,  the  British  dyes  will 
not  be  so  cheap  as  the  German,  owing  to  the  enormous  experience 
the  latter  have  behind  them.  On  the  other  hand,  in  our  gas- 
works we  have  a  great  deal  of  the  raw  product  necessary. 

My  own  feeling  is  that  a  large  portion  of  the  raw  products 
should  be  made  by  some  of  our  large  gas-works,  that  is  to  say, 
those  which  have  tar-distilling  plants.  They  have  there,  in  their 
works,  the  benzol,  toluol,  naphthalene,  anthracene,  etc.  With 
regard  to  the  last-named  substance — anthracene — the  British 
Alizarin  Company  can  probably  deal  with  it  better  than  anyone 
else,  but  they  will  require  increased  supplies. 

Why  should  not  nitrobenzene,  aniline,  nitrotoluene,  toluidine, 
the  naphthols,  naphthylamines,  phthalic  anhydride,  and  many 
other  substances,  which  are  the  raw  materials  for  the  colour 
works,  be  made  at  the  source  of  supply  of  the  raw  products  for 


312         THE   BRITISH   COAL-TAR   INDUSTRY 

their  manufacture  ?  About  10,000,000  gallons  of  benzene  are 
produced  annually,  and  before  the  war  two-thirds  of  this  went  to 
Germany,  a  portion  of  which  they  used  for  making  aniline. 

The  question  is  one  bristling  with  difficulties,  but  it  is  of 
instant  urgency.  Some  suggest  the  establishment  of  huge  works 
comparable  to  those  of  the  Badische  or  Meister,  Lucius  & 
BrUning  (forgetting  that  those  were  built  up  from  comparatively 
small  beginnings),  which  will  manufacture  every  type  of  colour 
and  also  fine  chemicals,  a  scheme  which  would  mean  in  the  long 
run  a  huge  financial  disaster.  Others  think  that  a  number  of 
small  firms  should  be  founded  which  would  manufacture  certain 
specific  ranges  of  colours.  This  certainly  is  more  feasible. 

My  own  feeling  is  that  those  firms  now  manufacturing  should 
enlarge  their  output  and  obtain  leave  to  work  certain  German 
patents  ;  that  many  of  the  raw  products  should  be  manufactured 
at  one  or  two  of  the  great  gas-works  who  might,  after  their  plant 
was  working,  also  make  certain  dyes  and  gradually  branch  out ; 
also  that  a  few  new  companies  with  carefully  thought-out  pro- 
grammes should  be  started. 

Now  in  connection  with  the  protection  of  the  industry  I  wish 
to  say  another  word.  We  will  presume  that  the  Government 
will  only  allow  the  use  of  British-made  dyes.  How  about  the 
other  consumers  ?  It  will  be  very  difficult  to  bind  them.  The 
best  solution  of  the  problem  would  be  to  give  them,  or  rather 
get  them  to  take,  an  interest  in  the  new  works,  or,  for  a  matter 
of  that,  in  the  old  ones.  This  was  done  by  the  Turkey  Red 
Dyers'  Association,  who,  in  order  to  prevent  the  manufacture  of 
alizarin  leaving  the  country,  founded  the  British  Alizarin  Com- 
pany, and  agreed  to  take  so  much  of  the  output.  They  were 
thus  not  dependent  upon  the  Germans,  and  also  had  an  interest 
in  the  manufacture  of  the  product.  Cannot  the  general  dyers  do 
something  similar  ? 

In  conclusion,  I  wish  to  say  just  one  word  as  to  the  revocation 
of  German  patents.  After  war  was  declared,  the  Home  Office 
revoked  all  German  and  Austrian  patents,  as  and  during  the 
continuance  of  the  war.  It  was  also  stated  that  in  certain  cases 
licences  would  be  granted  to  British  manufacturers  to  take  up 
and  work  these  patents.  I  was  informed  recently  by  an  eminent 
patent  lawyer  and  by  one  of  the  largest  patent  agents  in  London, 
that  the  granting  of  licences  is  practically  a  dead  letter.  Further, 
that  where  licences  have  been  granted,  a  royalty  is  reserved  for 


THE   INDUSTRY   IN    THIS   COUNTRY        313 

the  enemy,  and  there  is  no  certainty  that  those  who  have  obtained 
a  licence  during  the  war  will  be  allowed  to  work  the  patent  after 
the  declaration  of  peace. 

If  the  trade  is  to  come  to  this  country,  and  to  be  retained  by 
it,  it  is  of  vital  importance  that  these  matters  be  cleared  up,  and 
the  Government  must  help. 

DISCUSSION 

The  Chairman  (Mr  E.  HICKSON)  said  many  people  seemed  to 
think  that  the  colour  trade  in  Germany  had  been  fostered  and 
helped  by  the  Government  in  a  manner  which  was  quite  out  of 
proportion  with  the  truth,  and  those  of  them  who  had  seen  the 
little  jubilee  books  recently  issued  by  some  of  the  German  firms 
who  had  celebrated  their  fiftieth  anniversary  would  know  quite 
well  how  true  was  the  lecturer's  statement  that  most  of  these 
firms  started  on  the  most  insignificant  scale. 

The  Lord  Mayor  of  Leeds  (Mr  J.  E.  BEDFORD)  said  it  was 
particularly  interesting  to  hear  the  early  history  of  this  subject 
from  the  lips  of  one  who  bore  the  honoured  name  of  Perkin. 
He  thought  it  was  their  duty  to  recognise  the  scientific  and 
business-like  manner  in  which  Germany  had  conducted  and 
developed  this  important  industry.  When  the  present  crisis 
developed,  the  Government  had  very  promptly  set  up  at  the 
Board  of  Trade  a  Chemical  Products  Committee,  and  called 
together  eminent  business  and  scientific  men  to  discuss  the 
matter,  and  see  how  the  stoppage  of  the  textile  and  printing 
industries  could  be  avoided.  Some  of  them  had  taken  the  view 
that  it  would  be  absolutely  necessary,  in  order  to  build  up  and 
foster  this  industry,  for  the  Government  to  give  some  form  of 
protection.  He  himself  had  suggested  at  a  meeting  of  the  Leeds 
Chamber  of  Commerce  that  we  should  have  to  put  a  protective 
duty  of  about  25  to  30  per  cent,  on  imported  aniline  dyes,  and 
his  friends  had  reproached  him  with  the  fact  that  he  was  a 
Liberal  Free-trader,  and  was  now  turning  Conservative.  He 
had  replied  :  "  1  am  still  a  Free-trader,  but  in  extraordinary 
circumstances  and  in  time  of  war  you  must  adopt  war  methods.'' 
He  believed  they  had  in  England  a  sufficient  number  of  highly 
trained  chemists  to  develop  the  industry.  He  was  sure  that 
there  were  certain  of  the  simple  colours  which  could  be  tackled 
at  once  if  the  requisite  amount  of  capital  were  available. 


3 14         THE   BRITISH   COAL-TAR   INDUSTRY 

Professor  W.  M.  GARDNER  said  one  point  which  appeared  to 
him  worthy  of  mention,  and  which  was  not  included  in  the  list 
of  reasons  given  for  the  loss  of  the  industry,  was  perhaps  a 
fundamental  one.  Dr  Perkin  had  to  some  extent  touched  upon 
it  when  he  mentioned  that  in  the  development  of  the  synthesis 
of  indigo  upwards  of  £1,000,000  had  been  spent  in  experiment 
before  any  return  was  obtained.  It  appeared  to  him  that  this 
would  have  been  quite  impossible  in  England,  because  the 
investing  public  would  never  have  supported  an  expenditure  of 
any  such  sum.  Want  of  knowledge  and  of  interest  on  the  part 
of  the  investing  public  had  been  one  not  unimportant  cause  why 
companies  had  not  been  formed  for  the  development  of  the 
industry  in  this  country.  There  were  other  reasons  why  it  was 
peculiarly  difficult  to  regain  the  industry,  and  here  again  he 
should  like  to  touch  upon  a  point  which  the  lecturer,  no  doubt 
from  lack  of  time,  did  not  mention  ;  and  that  was  the  important 
way  in  which  secondary  and  subsidiary  interests  had  been  built 
round  the  great  coal-tar  colour  industry  of  Germany,  such  as 
the  manufacture  of  synthetic  medicines  and  synthetic  scents  and 
flavourings  on  the  one  hand,  and  the  manufacture  of  necessary 
reagents,  such  as  fuming  sulphuric  acid,  on  the  other.  These 
had  put  the  industry  in  Germany  in  an  extremely  strong  position, 
since  before  we  could  hope  successfully  to  compete  with  them 
we  should  have  to  launch  out,  not  only  in  the  manufacture  of 
colours,  but  in  many  other  directions,  so  that  altogether  an 
enormous  outlay  of  capital  would  be  required.  The  public  must 
recognise  that  it  was  a  most  complicated  question,  and  one  which 
would  require  not  only  great  enterprise  and  co-operation  on 
the  part  of  manufacturers  and  consumers,  but  would  inevitably 
require  assistance  from  the  Government. 

The  Lecturer  said  the  subject  was  so  big  that  he  was  afraid  of 
digressing  on  side  issues,  but  he  quite  agreed  with  Professor 
Gardner  that  one  of  the  reasons  why  the  industry  had  become  so 
great  in  Germany  was  the  working  up  of  by-products.  What 
was  waste  in  one  product  was  the  starting-point  in  making 
another  product,  and  if  they  were  going  to  manufacture 
successfully  in  this  country  they  must  pay  attention  to  that  fact. 
It  was  no  use  saying  they  would  manufacture  this  or  that  dye 
and  neglect  all  its  by-products.  If  they  did,  the  cost  of  the  dye 
would  be  out  of  all  proportion  to  its  cost  as  it  was  manufactured 
abroad. 


XXIV.:    1914 

THE  SUPPLY  OF  CHEMICALS  TO  BRITAIN 
AND  HER  DEPENDENCIES 

BY  SIR  WILLIAM  A.  TILDEN,  D.Sc.,  LL.D.,  F.R.S. 

(Journal  of  the  Royal  Society  of  Arts^  2Jth  November  1914,  p.  26) 

To  those  who  can  look  back  over  half  a  century,  the  progress 
of  scientific  and  industrial  chemistry,  and  the  relations  of  the  one 
to  the  other,  present  many  features  of  extreme  interest.  After 
the  days  of  Lavoisier,  and  during  the  earlier  part  of  the  nineteenth 
century,  the  foundations  of  theoretical  chemistry  were  laid  by  the 
efforts,  contemporaneous  but  independent,  of  the  chemists  of 
England,  France,  and  Sweden.  The  great  names  -associated 
with  the  movement  include  Davy,  Faraday,  Dalton,  Gay-Lussac, 
Dumas,  and  Berzelius.  There  were  no  German  chemists  of  the 
first  rank  in  those  days,  and  if  we  look  among  them  for  funda- 
mental discoveries  we  can  only  find  one  of  considerable  import- 
ance, namely,  the  discovery  of  isomorphism  by  Eilhard  Mitscher- 
lich  in  1819.  But  the  birth  of  Justus  Liebig  at  Darmstadt,  in 
1803,  gave  to  German  science  a  leader  whose  influence  stretches 
down  to  our  own  day,  and  is  felt  wherever  chemistry  is  studied  or 
practised.  The  department  of  organic  chemistry  has  been  the  field 
in  which  the  most  remarkable  successes  have  been  won,  though 
not  wholly,  as  sometimes  represented,  by  the  German  chemist. 

The  relation  of  optical  activity  to  atomic  constitution  was  the 
discovery  of  le  Bel,  a  Frenchman,  almost  simultaneously  with 
van  't  Hoff,  a  Dutchman,  and  the  application  of  their  theories 
to  the  phenomena  presented  by  compounds  other  than  those  of 
carbon  was  illustrated  in  the  first  instance  by  Smiles,  and  by  Pope 
and  Peachey,  all  of  whom  are  Englishmen.  It  will  also  be  only 
fair  to  state  that  while  we  readily  acknowledge  with  admiration 
the  brilliant  work  of  von  Baeyer  and  Emil  Fischer  in  connection 

315 


3i6         THE    BRITISH   COAL-TAR   INDUSTRY 

with  the  synthesis  of  indigo,  the  sugars  and  the  proteins,  the 
fundamental  principles  which  underly  all  chemical  theory  have 
been  established  almost  entirely  by  the  chemists  of  other  nations. 
It  is  only  necessary  to  recall  such  subjects  as  the  atomic  theory, 
the  periodic  law,  Faraday's  laws  of  electrolysis,  the  theory  of  free 
ions,  the  phenomena  of  radio-activity,  and  the  discovery  of  radium, 
to  show  that  in  laying  down  broad  general  principles  German 
chemists  have  not  usually  been  the  first  in  the  field,  though  at 
later  stages  they  have  shown  great  and  commendable  activity. 

Turning  now  to  the  position  of  industrial  chemistry,  a  single 
brief  quotation  from  the  "  Report  on  Chemical  and  Pharmaceutical 
Products  and  Processes"  in  the  International  Exhibition  of  1862, 
from  the  pen  of  A.  W.  Hofmann,  then  Professor  of  Chemistry 
in  the  Royal  College  of  Chemistry  and  Royal  School  of  Mines, 
London,  will  be  sufficient.  He  says  (p.  3)  :  "  The  contributions 
of  the  United  Kingdom,  and  in  particular  the  splendid  chemical 
display  in  the  eastern  annexe,  prove  the  British  not  only  to  have 
maintained  their  pre-eminence  among  the  chemical  manufacturers 
of  the  world,  but  to  have  outdone  their  own  admitted  superiority 
on  the  corresponding  occasion  of  1851." 

On  referring  to  the  table  of  statistics  which  appears  on  the 
same  page  of  the  report,  we  find  that  of  the  762  exhibitors  in 
the  class,  the  United  Kingdom  was  represented  by  200,  while 
Germany,  Austria,  the  Zollverein,  and  the  Hanse  towns  together 
mustered  only  136.  France  stood  next  with  115  exhibitors.  It 
will  be  remembered  that  at  the  date  of  the  exhibition  the  dis- 
covery of  the  so-called  aniline  colours  was  bearing  very  important 
industrial  fruit.  Mauve,  or  aniline  purple,  was  discovered  by 
W.  H.  Perkin  in  1856,  and  aniline  red  was  first  obtained 
industrially  by  Verguin  and  Renard  Freres  of  Lyons  a  few 
years  later. 

It  is  also  interesting  to  notice  that  among  the  early  investi- 
gators and  patentees  of  processes  connected  with  the  production 
of  colour  from  coal-tar  hydrocarbons,  only  English  and  French 
names  are  to  be  found,  with  the  significant  exceptions  of  Hofmann 
and  Caro,  both  of  whom  were  at  that  period  resident  in  England. 
At  this  time  synthetical  chemistry  in  the  modern  sense  was  as  yet 
unpractised  because  unknown.  Such  an  important  substance  as 
salicylic  acid,  for  example,  was  a  mere  laboratory  product,  obtain- 
able only  from  natural  sources. 

But   the  activity  of   the  chemical  industries  in  the    United 


THE   SUPPLY   OF   CHEMICALS   TO   BRITAIN     317 

Kingdom  is  not  to  be  measured  only  by  reference  to  subjects 
such  as  those  of  the  coal-tar  colours,  nor  by  the  number  of 
exhibitors  in  an  international  exhibition  even  at  that  early  period 
in  the  history  of  exhibitions,  at  which  manufacturers  were  far 
more  eager  to  find  a  place  than  they  have  been  in  more  recent 
times.  Statistics  in  relation  to  the  development  of  the  alkali 
trade  show  how  rapidly  the  production  of  what  are  called  "  heavy 
chemicals  "  was  proceeding  at  this  period.  Figures  derived  from 
returns  collected  by  Mr  Christian  Allhusen  from  8 1  per  cent,  of 
the  manufacturers  in  the  United  Kingdom,  immediately  after  the 
first  Great  Exhibition,  are  shown  below.  These  may  be  compared 
with  statistics  prepared  by  Mr  W.  Gossage  for  the  year  1861, 
immediately  before  the  Exhibition  of  I8621 : — 


1852. 

1861. 

Tons. 

Tons. 

Soda  ash        .... 

71,193 

156,000 

Soda  crystals  .... 

61,044 

104,000 

Bicarbonate    .... 

5>762 

13,000 

Bleaching  powder  . 

13,100 

20,000 

The  value  of  these  products  for  1852  was  estimated  at  about 
ij  million  pounds,  while  the  value  of  the  products  of  1861  was 
calculated  by  Mr  Gossage  at  upwards  of  two  millions  sterling. 

The  Board  of  Trade  has  recently  issued  a  Bulletin  concerning 
German  competition  in  the  United  Kingdom  market,  and  on 
page  2  we  find  the  statement  that  the  soda  compounds,  excluding 
chromates  and  bleaching  powder,  produced  in  the  United 
Kingdom  in  the  year  1907,  are  valued  at  £3,390,000.  The  im- 
ports from  Germany  in  1912  are  valued  at  only  £8700.  As 
to  bleaching  materials,  the  product  of  the  United  Kingdom  for 
1907  is  estimated  at  £527,000,  while  the  import  from  Germany 
for  1912  was  £44,600. 

From  these  figures  the  easy  deduction  is  made  that  "the 
imports  of  these  chemicals  into  the  United  Kingdom  from 
Germany  are  relatively  insignificant  when  compared  with  the 
output  of  the  same  articles  in  this  country.  It  is  clear  that  in 
these  particular  lines  British  manufacturers  have  no  need  to 
fear  German  competition  in  the  home  market." 

1  Gossage's  History  of  the  Soda  Manufacture. 


318         THE   BRITISH   COAL-TAR   INDUSTRY 

Similar  remarks  apply  to  aluminous  compounds,  coal-tar 
products  not  dyes,  the  cyanides,  sulphuric  acid,  and  other  acids 
for  which  the  Bulletin  may  be  consulted.  It  thus  appears  that 
the  British  manufacturers  of  sulphuric  acid  and  soda,  from  the 
early  times  of  a  century  ago,  have  been  able,  up  to  the  present, 
to  hold  their  own  against  foreign  competition,  and  have  thus 
added  substantially  to  the  revenues  and  well-being  of  their 
country. 

The  immense  advances  in  every  direction  made  in  all 
civilised  countries  have  brought  demands  in  steadily  increasing 
quantities  for  a  variety  of  materials  of  which  many  were  unknown 
to  the  generations  immediately  preceding  our  own.  These  are 
almost  all  the  outcome  of  the  progress  in  our  own  time  of 
chemical  knowledge.  Since  the  introduction  of  the  coal-tar 
dyes  the  development  of  chemical  theory  has  rendered  possible 
the  production  in  the  laboratory  of  a  large  number  of  organic 
substances  which  are  either  identical  with  compounds  already 
known  as  occurring  in  Nature,  or  from  their  ascertained  physio- 
logical action'  have  added  incalculably  to  the  resources  of  the 
physician  and  surgeon  in  relieving  pain  and  in  curing  disease. 
These  include  not  only  drugs  for  internal  administration,  but 
antiseptics,  the  use  of  which  was  only  beginning  to  be  recognised 
at  the  time  of  the  Exhibition  in  1862  (Hofmann's  Report, 
pp.  104-105). 

To  these  must  be  added  essential  oils  and  other  volatile 
aromatic  substances,  the  application  of  which  to  perfumery  and 
flavouring  has  undergone  a  stupendous  development  during  the 
last  thirty  years. 

The  innumerable  applications  of  photography  have  also 
led  to  a  deniand  for  developing,  fixing,  and  toning  materials,  as 
well  as  for  plates  and  films  on  a  very  large  scale. 

The  arts  of  peace  as  well  as  the  operations  of  war  have  also 
led  to  the  production  of  explosives  of  many  new  types  formerly 
unknown. 

There  is  also  another  department  of  business  which  requires 
notice,  and  that  is  the  demand  for  pure  chemical  reagents  for 
analysis  and  research,  which  has  increased  to  an  extent  very 
difficult  to  calculate,  but  is  manifestly  very  large.  The  modern 
university  and  technical  colleges,  nearly  the  whole  of  which  have 
come  into  existence  within  the  last  forty  years,  the  large  body 
of  Public  Analysts  appointed  under  the  Sale  of  Food  and  Drugs 


THE   SUPPLY   OF   CHEMICALS   TO   BRITAIN     319 

Act,  1875,  the  establishment  in  nearly  all  the  public  schools  and 
high  schools  of  laboratories  for  teaching  chemistry,  as  well  as 
the  numerous  technical  laboratories  connected  with  such  in- 
stitutions as  the  Government  Laboratory,  the  National  Physical 
Laboratory,  the  Metropolitan  Water  Board,  and  many  others, 
afford  sufficient  evidence  that  there  are  several  hundreds  of 
chemical  laboratories  distributed  over  the  United  Kingdom  in 
which  pure  chemicals  are  required  for  analytical  purposes. 

Now,  leaving  to  the  department  of  "  heavy  chemicals "  all 
such  things  as  agricultural  and  horticultural  washes,  coarse  disin- 
fectants and  artificial  manures,  the  question  arises  :  How  do 
we  in  England  stand  in  regard  to  the  supply  of  drugs,  dyes, 
photographic  chemicals,  and  perfumes  at  a  time  when  many  of 
these  things  are  very  urgently  needed  ? 

It  may  be  safely  asserted  that  the  sources  of  supply  of  all 
these  materials  in  the  United  Kingdom  are  seriously  inadequate. 
And,  further,  we  may  point  to  the  acknowledged  fact  that  many 
of  the  dyes,  and  nearly  all  the  synthetic  drugs  and  photographic 
materials  have  been  systematically  imported  from  Germany. 

The  Annual  Statement  of  the  Board  of  Trade  (p.  108)  shows 
that  in  1913  we  imported  from  Germany  : — 

£ 

Alizarin  and  anthracene  dyes  .  .  .  .  271,119 
Aniline  and  naphthalene  dyes  .  .  .  1,382,478 
Synthetic  indigo 76,681 

1,730,278 

Under  the  head  of  "  Drugs,  unenumerated,  including 
Medicinal  Preparations  "  (p.  107),  out  of  a  total  of  imports  from 
foreign  countries  and  from  British  possessions  amounting  to 
£1,302,860,  more  than  one-fourth,  or  to  the  value  of  £332,464, 
was  in  1913  received  from  Germany.  From  this  is  to  be 
deducted  the  inconsiderable  amount  of  dyes  and  other  chemicals 
from  coal-tar,  valued  at  £24,691,  exported  in  1913  to  Germany 
(p.  300).  According  to  the  Final  Report  on  the  First  Census  of 
Production  of  the  United  Kingdom  for  1907  (p.  547),  this 
country  made  139,000  cwt.  of  coal-tar  dyes,  valued  at  £373,000, 
of  which  practically  the  whole  was  consumed  at  home. 

As  to  fine  chemicals  for  analysis  and  for  research,  there  are 
no  figures  available,  but  it  may  safely  be  said  that  there  has  been 
no  appreciable  production  of  these  things  in  this  country.  If 


320         THE   BRITISH   COAL-TAR   INDUSTRY 

such  a  statement  is  met  by  protests  from  manufacturers  who  pro- 
fess to  supply  these  materials  it  is  only  necessary  to  refer  to 
the  experience  of  analysts  and  directors  of  research  laboratories, 
which  has  compelled  many  of  them  to  resort  habitually  to 
German  makers  for  their  supplies  of  trustworthy  reagents. 

If  we  are  ever  to  be  in  a  position  to  supply  ourselves  and 
our  dependencies  with  the  dyes,  the  drugs,  and  the  rest  of  the 
fine  chemicals  required  in  our  work,  it  will  only  be  achieved  after 
a  careful  review  of  the  circumstances  which  led  to  the  removal 
of  the  industries  from  this,  the  country  in  which  many  of  them 
originated,  together  with  a  determination  to  take  to  heart  the 
lessons  of  the  past. 

A  chemical  manufacturer,  discussing  the  neglect  of  fine 
chemicals  in  this  country,  recently  made  the  remark  :  "  What 
does  it  matter,  if  we  are  making  money  ? "  I  venture  to  say 
that  that  view  expresses  neither  patriotism  nor  common  sense. 
For  the  same  principles  which  have  served  as  the  basis  of  the 
German  success  in  relation  to  dyes  and  fine  chemicals  apply 
equally  to  the  production  of  heavy  chemicals,  and  already 
German  chemists  have  been  boasting  that,  having  secured  the 
trade  in  the  former,  they  are  about  to  attack  the  latter. 

The  export  trade  in  sulphuric  acid  alone  is  already  three 
times  as  great  from  Germany  (1912)  as  from  the  United  Kingdom 
(1913),  as  shown  by  the  figures  given  in  the  recent  Bulletin 
issued  by  the  Board  of  Trade  (Commercial  Intelligence  Branch, 
October  1914). 

The  recent  success  of  Professor  Haber,  of  Karlsruhe,  in 
the  synthetical  production  of  ammonia  from  hydrogen  and 
atmospheric  nitrogen,  a  process  which  has  been  put  into  opera- 
tion on  an  industrial  scale  by  the  Badische  Company,  ought 
surely  to  carry  something  significant  to  the  unprejudiced  mind. 
Neither  is  it  superfluous  to  point  to  the  extensions  taking  place 
in  several  countries  of  operations  in  which  the  nitrogen  of  the 
atmosphere  is  being  fixed  in  the  form4  of  cyanamide,  of  nitrites 
and  nitrates  in  which  the  industrial  lead  has  been  taken  by 
Germany,  which  also  supplies  a  large  proportion  of  the  capital, 
though  at  present  not  to  the  exclusion  of  the  British. 

The  extent  to  which  the  German  chemist  arrogates  to  himself 
the  whole  field  of  scientific  and  industrial  chemistry  is  illustrated 
in  the  report  (given  in  full  of  Nature,  Ixxxv.  p.  558)  of  a  lecture 
given  by  Professor  Emil  Fischer  on  nth  January  1911,  in  the 


THE   SUPPLY   OF   CHEMICALS   TO   BRITAIN     321 

presence  of  the  Emperor,  on  the  occasion  of  the  inauguration  of 
the  Kaiser  Wilhelm  Gesellschaft  zur  Fflrderung  der  Wissen- 
schaften.  It  is  at  least  unpleasant  to  hear  of  a  man  so  eminent 
as  Professor  Fischer,  and  so  worthy  of  respect,  treating  the 
subjects  of  his  discourse  as  though  every  one  of  them  had 
originated  and  been  developed  in  Germany.  Perkin  is  indeed 
referred  to  as  the  discoverer  of  mauve,  but  every  other  foreign 
name  is  omitted. 

If  I  now  try  to  recall  some  of  the  circumstances  which  led 
to  the  gradual  transference  of  the  colour  industry  from  this 
country  to  Germany,  and  the  failure  to  establish  here  any 
appreciable  production  of  the  synthetical  drugs  and  other 
chemicals  now  so  urgently  needed,  it  will  not  be  the  first  time 
the  facts  have  been  stated  and  the  obvious  conclusions  deduced 
therefrom. 

All  the  substances  referred  to  belong  to  the  department  of 
organic  chemistry,  and  it  might  perhaps  be  supposed  that  neglect 
of  this  branch  of  the  science  by  the  chemists  of  this  country  was 
the  cause  of  the  loss  of  business.  When  Hofmann  was  un- 
fortunately allowed  to  leave  the  College  of  Chemistry  to  return 
to  his  own  country,  a  check  was  for  some  time  observable  in  the 
output  of  research  among  us,  but  it  must  be  remembered  that 
the  number  of  institutions  in  all  countries  in  which  the  study 
of  chemistry  was  pursued  was  then  relatively  small.  Even  in 
Germany  the  Chemical  Society  in  Berlin  did  not  come  into 
existence  till  1867,  anc^  UP  to  tnat  time  there  had  been  no 
laboratory  for  practical  instruction  in  chemistry  in  the  university 
of  that  city. 

For  the  last  thirty  years,  however,  the  progress  of  research 
in  this  country  has  gone  forward  at  an  increasing  rate,  though 
still  less  rapidly  than  in  Germany.  The  slow  development  of 
chemical  teaching  and  research  in  this  country  was  attributed 
by  many  people  to  the  anti-scientific  influences  at  work  in  our 
universities,  and  especially  the  older  universities.  This  point 
of  view  was  exposed  very  clearly  and  forcibly  by  the  late  Sir 
William  Perkin  in  presidential  addresses  delivered  to  the 
Chemical  Society  and  the  Society  of  Chemical  Industry  in  1885 
(see  p.  75,  ante).  And  up  to  this  time  it  would  be  indeed  difficult 
to  exonerate  Oxford  and  Cambridge  from  responsibility  in  the 
evil  example  shown  by  those  great  seats  of  learning.  But  since 
that  day  many  changes  have  taken  place,  and  great  advances 

21 


3*2         THE  BRITISH   COAL-TAR   INDUSTRY 

have  been  made.  What  is  wanted  in  the  British  universities 
is,  first  of  all,  that  no  man  shall  in  future  be  appointed  to  a 
professorship,  or  indeed  to  any  teaching  post  in  connection  with 
physical  or  natural  science,  who  does  not  show  his  ability  to 
instruct  in  the  higher  branches  of  his  subject  by  the  character 
of  the  researches  which  he  continues  to  carry  out  during  his 
tenure  of  office  ;  and,  secondly,  such  a  change  in  the  curriculum 
and  endowments  that  there  may  be  not  only  a  supply  of 
instruments  and  materials  but  a  sufficient  body  of  trained 
assistants  in  the  form  of  advanced  students  to  enable  the 
professor  to  pursue  without  delay  any  promising  line  of 
investigation. 

Notwithstanding  the  difficulties  which  stand  in  the  way  the 
scientific  chemists  of  this  country  are,  however,  not  idle. 
Evidence  of  this  may  be  seen  in  the  Transactions  of  the  Chemical 
Society ,  the  volume  of  which  for  1913  contains  238  papers 
extending  over  more  than  2300  pages.  And  when  it  is 
remembered  that  these  papers  have  survived  the  severe 
censorship  exercised  by  the  Publication  Committee  of  the 
Society  the  result  must  be  considered  encouraging.  It  appears, 
then,  that  it  is  not  to  the  scientific  part  of  the  chemical  world 
that  blame  attaches  in  recent  times. 

Forty  years  ago  it  would  be  safe  to  say  that  there  were 

practically  no  chemists  engaged  in  the  direction  of  the  chemical 

works  or  this  country,  and  by  chemists  I  mean  fully  qualified 

scientific  men.     Probably  in  the  palmy  days  of  colour-making  it 

would  have  been  difficult  to  meet  with  a  British  manufacturer 

who  had  ever  heard  of  Kekule's  benzene  theory,  or  would  have 

thought  it  worthy  of  a  moment's  notice  by  a  practical  man. 

And  yet  at  the  Kekule  Jubilee  in   1890  a  representative  of  the 

German  coal-tar  colour  industry  declared  that  the  prosperity  of 

Germany  in  this  direction  was  primarily  due  to  this  theoretical 

conception.    Even  in  much  later  times  the  chemical  manufacturer 

in  this  country  has  repeatedly  had  facts  laid  before  him  which 

ought  to  have  attracted  his  serious  attention.     One  of  the  most 

convincing  statements  was  laid  before  this  Society  by  Professor 

Meldola  on   I3th  May  1886  (see  p.  121,  ante\  and  one  would 

suppose  that  the  figures  then  given  would  have  been  sufficient 

to  create  well-founded  alarm.     For  he  showed,  on  the  testimony 

of   a   considerable   number   of   prominent  English   dyers,   that 

already  about  nine-tenths  of  the  colours  employed  by  them  were 


THE   SUPPLY   OF   CHEMICALS   TO   BRITAIN     323 

imported  from  Germany.  Again,  in  a  lecture  given  before  the 
British  Association  in  1901,  on  the  "Relative  Progress  of  the 
Coal-tar  Industry  in  England  and  Germany  during  the  Past 
Fifteen  Years  "  (see  p.  189,  ante).  Professor  Green  showed  clearly 
the  steady  increase  in  the  imports  of  dyestuffs  from  Germany 
into  England,  and  the  steady  decline  in  the  production  of  similar 
materials  in  England. 

Finally,  we  have  the  fact  known  to  all  the  world  that  one 
of  the  most  notable  triumphs  of  German  chemical  industry  is 
the  production  of  synthetic  indigo  made  from  naphthalene  on 
a  scale  so  large  as  to  have  almost  driven  the  Indian  planter  from 
the  field.  In  this  case  we  have  over  again  a  story  nearly 
corresponding  to  the  history  of  the  introduction  of  artificial 
alizarin  in  1869,  an  event  which  was  speedily  followed  by  the 
abandonment  of  the  cultivation  of  madder  in  the  south  of 
France  and  elsewhere.  And  to-day  we  learn  from  the  Board 
of  Trade  Statement  for  1913  that  we  imported  indigo  from 
Germany  to  the  value  of  ^76,681,  while  the  value  of  the 
natural  indigo  from  India  has  declined  from  ^124,1 12  in  1909 
to  ^48,208  in  1913.  As  to  the  cause  of  this  serious  reduction 
of  chemical  business  authorities  are  unanimous. 

Perkin,  in  the  address  to  the  Chemical  Society  already  quoted, 
attributed  the  success  of  the  German  industries  to  the  employ- 
ment of  high-class  chemists  (Trans.  Chem.  Soc.,  xlv.  [1884], 
p.  219  et  seq.}. 

The  same  view  was  expressed  by  Professor  Meldola  in  his 
paper  before  this  Society  in  1886.  "The  strength  of  our 
competitors,"  he  says,  "  is  in  their  laboratories  and  not,  as  here, 
on  the  exchanges." 

Professor  Green  stated  as  his  opinion,  in  the  lecture  referred 
to,  that  the  remedy  for  the  present  state  of  affairs  can  only  be 
found  in  a  better  appreciation  of  the  value  of  science  throughout 
the  length  and  breadth  of  the  land,  and  that  it  is  not  so  much 
the  education  of  our  chemists  which  is  at  fault  as  the  scientific 
education  of  the  public  as  a  whole.  Nor  can  much  improvement 
be  expected  till  the  public,  including  manufacturers,  can  be 
disabused  of  the  fallacy  that  a  year  or  two  of  technical  training 
pumped  into  an  ignorant  schoolboy  will  produce  a  better  works 
chemist  than  a  university  course  of  scientific  study  laid  upon  the 
foundation  of  a  good  general  education. 

If  these  are  supposed  to  be  merely  the  prejudiced  opinions 


324 


THE   BRITISH   COAL-TAR   INDUSTRY 


of  British  chemists,  the  sentiments  expressed  by  German  manu- 
facturers themselves  may  be  appealed  to. 

In  1900  a  lecture  was  delivered  on  the  occasion  of  the 
opening  of  the  Hofmann  House  in  Berlin  by  Dr  H.  Brunck, 
since  1884  chief  technical  director  of  the  Badische  Company,  on 
the  "History  of  the  Development  of  the  Manufacture  of  Indigo  " 
(see  p.  204,  ante).  This  lecture,  in  the  form  of  the  English 
version  issued  by  Dr  Brunck,  may  be  fairly  regarded  as  a  sermon 
preached  to  British  manufacturers.  Its  perusal  will  convince 
anyone  that  the  success  which  has  been  achieved  is  the  reward 
of  long-sustained  investigation  in  the  laboratory  of  the  scientific 
chemist,  and  to  do  justice  to  this  conviction  I  wish  every  chemical 
employer  in  this  country  could  be  induced  to  read  the  weighty 
and  eloquent  words  of  the  author.  He  would  then  perceive 
that  to  permanent  industrial  success  there  is  only  one  road,  and 
that  the  way  pointed  by  science. 

I  will  content  myself  with  quoting  only  a  passage  or  two 
from  Brunck's  lecture  : — 

"  With  grateful  admiration  and  reverence  do  we  recall  those 
ever  memorable  masters,  Kekul6  and  A.  W.  von  Hofmann, 
whose  gifted  achievements  have  laid  the  foundations  of  our 
industry.  And  when  we  look  back  at  all  the  technical  achieve- 
ments we  also  gratefully  recall  the  fertile  discoveries  of  Graebe 
and  Liebermann,  of  Peter  Griess,  and  the  beautiful  researches 
of  Emil  and  Otto  Fischer,  of  O.  N.  Witt,  and  the  numerous 
other  investigations  conducted  in  our  university  laboratories, 
which  have  acted  as  incentives  for  chemical  industry,  and  have 
furnished  the  foundation  for  renewed  progress.  But  first  and 
foremost  we  are  impressed  by  the  mighty  influence  of  the 
investigations  of  A.  von  Baeyer,  to  whom  the  coal-tar  colour 
industry  is  indebted  for  a  great  number  of  important  achieve- 
ments, and  who  himself  has,  to-day,  unfurled  before  you  the 
picture  of  a  magnificent  scientific  creation,  from  which  it  was 
possible  for  chemical  industry  to  construct  and  develop  one  of 
its  grandest  achievements. 

"  But  this  infant  industry  was  no  longer  content  to  be 
dependent  on  the  gifts  which  were  made  to  it  from  various 
scientific  sources.  Renowned  investigators  placed  themselves 
entirely  at  the  disposal  of  chemical  industry  ;  young  men  in 
great  numbers  devoted  themselves  to  it,  and  grew  up  with  it 
in  enthusiastic  and  self-directed  activity.  Such  men  as  Caro, 


THE   SUPPLY   OF   CHEMICALS  TO   BRITAIN     325 

Glaser,  Martius,  and  later  on  Laubenheimer,  Duisberg,  Bernthsen, 
and  many  others,  introduced  the  spirit  of  scientific  investigation 
into  industrial  practice."  And,  in  conclusion,  he  says  :  "  You 
have  seen  that  this  new  industry  is  not  an  unexpected  gift  fallen 
from  the  heavens,  but  that  in  order  to  complete  the  task  the 
intellectual  labour  and  the  industry  of  many  men  had  to  be 
co-ordinated  in  an  organised  attempt  to  attain  a  definite  object 
for  a  number  of  years  and  throughout  a  considerable  period 
when  success  could  by  no  means  be  regarded  as  certain.  The 
pre-requisites  for  practical  indigo  synthesis  were  supplied  by  the 
results  of  long  years  of  scientific  labour." 

In  the  semi-annual  report  for  April  1903  issued  by 
Schimmel  &  Co.,  the  famous  manufacturers  of  essential  oils, 
there  are  some  figures  which  show  the  increase  of  chemical 
works  in  Germany  and  the  great  increase  in  the  numbers  of 
qualified  workmen  employed  therein,  on  which  the  firm  makes 
the  following  remark  : — "  The  foregoing  figures  show  clearly 
that  the  German  chemical  industry  has  passed  intact  through  the 
economic  crisis  of  the  last  few  years.  Further,  there  are  no 
grounds  for  fearing  that  it  will  be  outstripped  by  competition 
from  abroad,  so  long  as  the  German  universities  possess  such 
eminent  representatives  of  chemical  science." 

It  is  now  time  to  consider  what  ought  to  be  done  and  what 
it  is  possible  to  do  in  this  country  to  remove  reproach  from 
British  chemical  industry,  and  to  render  the  Empire  independent 
of  supplies  from  foreign  sources. 

We  need  many  first-rate  chemists,  a  few  engineers,  plenty  of 
capital,  and  some  good  men  of  business.  A  combination  of  these 
elements  in  due  proportion  is  certain  of  success,  and  the  time, 
though  so  unhappy  for  the  world,  is  favourable  for  this  enterprise. 

Inasmuch  as  the  functions  of  each  and  the  best  way  of  com- 
bining them  have  already  been  settled  in  practice  on  the  Continent, 
it  is  to  be  hoped  that  the  ancient  precept  about  being  taught  by 
the  enemy — -fas  est  et  eb  hoste  doceri — will  not  be  forgotten.  For 
there  can  be  no  doubt  that  the  principle  acted  on  in  all  German 
chemical  factories,  namely,  the  employment  of  the  best  available 
scientific  skill  and  the  constant  appeal  to  scientific  research,  has 
been  the  secret  of  their  success. 

In  the  British  colleges  and  universities  there  are  many  able 
young  chemists,  but  many  more  are  required.  Here  education 
and  industry  interact  on  each  other.  If  the  demand  for  scientific 


326         THE   BRITISH   COAL-TAR   INDUSTRY 

assistance  were  more  general,  the  supply  of  well-qualified  men 
would  soon  be  greatly  increased,  and  greater  attention  given  by 
the  teachers  to  the  industrial  side  of  the  subject.  At  present 
other  professions  in  which  the  prospects  are  more  alluring  attract 
into  other  lines  of  work  much  of  the  talent  of  the  country. 
This,  however,  is  not  to  be  interpreted  as  meaning  that  there  is 
not  now  a  supply  of  able  young  chemists  sufficient  for  immediate 
needs.  The  difficulty  is  to  induce  chemical  manufacturers  to 
treat  them  reasonably.  The  pay  offered  is  generally  insufficient, 
and  though  conditions  are  somewhat  improved  of  late  years,  the 
employer  too  often  expects  immediate  profitable  returns  from  the 
engagement  of  a  scientific  man.  In  the  Badische  works  at 
Ludwigshafen  the  plan  has  been  to  engage  university  men  on 
the  recommendation  of  their  professors  for  a  term  of  years,  at  a 
salary  which  will  enable  the  new  members  of  the  staff  to  live  at 
least  modestly.  I  am  told  that  in  some  American  works  the  same 
system  has  been  adopted.  These  young  men  are  placed  in  the 
research  laboratory  under  the  chief  chemist  controlling  the  de- 
partment of  manufacture  selected,  and  it  is  not  expected  that  they 
will  accomplish  anything  very  remunerative  at  first.  But  their 
future  depends  on  their  ability  and  activity,  and  they  act 
accordingly. 

Then  there  is  the  position  to  be  accorded  to  the  engineer. 
He  is,  of  course,  indispensable  ;  but  the  part  he  should  play  in 
the  works  depends  on  the  nature  of  the  processes  involved.  So 
far  as  relates  to  buildings  and  other  structures,  to  supplies  of 
water,  fuel,  power,  and  electricty,  the  engineer  has  the  field  to 
himself,  but  the  operations  in  which  materials  are  to  be  employed 
in  producing  and  controlling  chemical  reactions  which  lead  to  the 
desired  product  belong  to  the  chemist,  and  here  he  ought  to  be 
supreme.  In  some  of  the  old-established  operations  an  engineer 
with  an  elementary  knowledge  of  chemistry  may  carry  on  fo  a 
time,  but  in  these  days  a  chemist  with  the  most  extensive  and 
intimate  knowledge  of  physical  chemistry  is  necessary  if  these 
processes  are  to  continue  to  be  profitable.  As  to  the  production 
of  dyes  and  other  organic  synthetical  products,  the  operations 
involved  are  in  many  cases  so  nearly  similar  to  laboratory  pro- 
cesses that  the  chemist  requires  very  little  assistance  from  the 
engineer. 

As  to  capital,  it  is  necessary  to  remember  that  it  will  have  to 
be  provided  liberally.  A  single  fact  mentioned  in  Brunck's 


THE   SUPPLY   OF   CHEMICALS   TO   BRITAIN     327 

lecture  on  indigo,  given  already  fourteen  years  ago,  shows  the 
spirit  in  which  the  German  manufacturers  attacked  the  problem 
of  the  industrial  production  of  this  one  colouring  matter.  They 
had  then  invested  about  £900,000  for  this  purpose. 

The  works  of  the  Badische  Anilin-  u.  Soda-Fabrik  at  Ludwigs- 
hafen  are  arranged  on  a  plan,  which  clearly  recognises  the  in- 
separability of  research  and  manufacture.  A  number  of  rect- 
angular buildings,  four  storeys  high,  are  so  arranged  that  the 
railway  lines  may  traverse  the  works  in  two  directions  at  right 
angles  to  each  other.  Each  building  is  devoted  to  the  production 
of  one  substance  or  closely  allied  group  of  substances.  The  top 
floor  is  occupied  by  the  laboratory  of  the  chief  chemist  attached 
to  that  department,  with  several  assistants.  Below  is  found  an 
intermediate  floor  where  processes  previously  tested  in  the 
laboratory,  or  suggested  as  the  result  of  research,  may  be  tried 
on  a  scale  sufficiently  large  to  determine  their  practicability  before 
being  transferred  to  the  lower  floors  where  the  actual  manufacture 
is  conducted.  I  doubt  if  anything  so  complete  or  so  commercially 
successful  exists  elsewhere  in  the  world. 

How  many  chemical  manufacturers  among  us  can  boast 
that  they  regard  science  in  a  light  so  serious  as  to  have  pro- 
vided in  their  works  a  properly  equipped  laboratory  with  a  com- 
petent staff  whose  occupation  is  not  confined  to  the  analytical 
testing  of  materials  or  products,  but  extends  to  the  systematic 
endeavour  to  introduce  improvements  into  old  methods  or  the 
discovery  of  new  ones  ?  A  few  such  enlightened  firms  do  exist, 
but  the  figures  quoted  show  how  much  mischief  has  already 
been  done. 

A  variety  of  other  questions  have  recently  been  raised  in  view 
of  the  circumstances  which  have  been  forced  on  our  notice  by  the 
war.  There  is  not  time  for  the  discussion  of  the  state  of  the  law 
as  to  patents,  but  a  couple  of  sentences  in  Schimmers  report  for 
April  1908  show  that  "great  alarm  has  been  caused  in  the  whole- 
sale chemical  industry  of  Germany  by  the  new  British  Patent 
Act,  which  came  into  force  on  ist  January  1908,  according  to 
which  every  patent  may  be  declared  void  if  it  is  exclusively 
exercised  abroad  without  sufficient  grounds.  Many  firms  are 
thereby  compelled  to  transfer  a  part  of  their  production  to  the 
United  Kingdom,  a  fact  which,  in  the  interests  of  many  thousands 
of  German  workmen,  is  sincerely  to  be  regretted. " 

With  regard  to  duty-free  alcohol,  I  am  informed,  on  the  best 


328         THE   BRITISH   COAL-TAR   INDUSTRY 

authority,  that  the  regulations  in  this  country  are  now  compar- 
able with  those  of  the  German  Government,  and  that  there  is 
very  little  ground  for  complaint.  In  the  vast  majority  of  cases 
suitably  denatured  alcohol  can  be  employed  without  loss  or 
inconvenience. 

There  has  been  a  good  deal  of  discussion  on  the  subject  of 
trade-marks  and  proprietary  names,  much  of  which  I  regard  as 
futile.  With  regard  to  drugs,  there  should  be  no  great  difficulty 
in  instructing  the  medical  profession  in  those  comparatively  few 
cases  in  which  the  names  are  changed. 

In  conclusion,  two  remarks  only  require  to  be  made.  The 
establishment  of  what  will  be  practically  a  new  industry  in  this 
country  will  require  consideration  and  assistance  from  the  State, 
if  it  is  to  survive  the  period  of  fierce  competition  which  will 
follow  the  conclusion  of  the  war.  Encouragement  is  already 
promised  to  the  dye  industry,  in  the  form  of  definite  financial 
aid  to  be  given  by  Government.  But  remembering  that  the 
colour-maker  is  dependent  on  the  production  of  many  chemi- 
cals, which  represent  intermediate  stages  in  the  processes  which 
lead  from  the  raw  materials  to  the  finished  product,  and  that  the 
production  of  these  chemicals  is  naturally  associated  with  other 
chemical  manufactures,  it  is  to  be  hoped  that  the  temporary 
production  will  be  extended  beyond  the  immediate  field  of  the 
colour-maker. 

The  other  remark  may  raise  a  smile  on  the  part  of  those 
business  men  who  are  moved  only  by  commercial  considerations. 
There  will  be  a  great  temptation  when  the  war  is  over  to  resume 
former  business  relations  with  the  enemy.  The  German  chemical 
manufacturers  have  a  powerful  organisation  and  many  years  of 
experience  behind  them.  Let  them  keep  any  markets  they  can 
retain  outside  the  British  Empire,  but  every  man  who  cares  for 
his  country  will  surely  demand  that  business  at  home  shall  be 
limited  to  British  goods. 

DISCUSSION 

The  Chairman  (Sir  WILLIAM  RAMSAY),  in  opening  the  dis- 
cussion, said  the  paper  emphasised  what  we  had  been  told  so 
often  during  past  years,  that  too  little  attention  had  been  paid 
to  the  scientific  side  of  chemical  manufacture  in  Great  Britain. 
But  there  were  two  aspects  of  the  question  which  had  not,  he 


THE   SUPPLY   OF   CHEMICALS   TO   BRITAIN     329 

thought,  been  sufficiently  touched  on.  The  first  aspect  was  as 
follows  :  Trade  was  regarded  in  Germany  as  a  war  ;  all  means 
of  conquest  were  looked  on  as  permissible.  At  the  annual 
meeting  of  the  Society  of  Chemical  Industry  in  1903,  he  had 
said  :  "  It  was  the  Prussians  who  first  showed  how  a  modern 
army  should  be  organised  .  .  .  they  have  at  Berlin  a  council 
which  arranges  each  particular  of  each  possible  campaign  ;  the 
men  are  known  who  will  take  the  command,  and  from  rank  to 
rank  the  knowledge  is  spread  as  to  what  particular  part  each 
officer  and  each  man  will  have  to  play  in  the  campaign.  The 
matter  is  not  left  to  chance.  .  .  .  An  exactly  similar  policy  is 
being  pursued  by  Germany  in  the  matter  of  industry.  It  would 
be  curious  if  it  had  not  occurred  to  the  persons  who  are  respons- 
ible for  the  military  organisation  of  Prussia  that  a  similar  policy 
is  applicable  to  commerce.  It  would  be  remarkable  if,  having 
succeeded  so  well  in  their  military  organisation,  no  attempt  had 
been  made  to  establish  a  similar  commercial  organisation  ;  and 
we  shall  not  go  wrong  if  we  assume  that  there  is  a  council  whose 
proceedings  are  kept  quiet  but  which  takes  into  consideration  the 
statistics  obtainable,  and  as  far  as  possible  legislates,  or  endeavours 
to  legislate,  on  the  basis  of  these  statistics.  Where  fiscal  duties 
are  found  to  be  wanted,  such  a  council  puts  them  on  ;  where 
there  is  an  advantage  in  taking  them  off,  they  take  them  off. 
Where  cheap  transit  is  possible,  they  let  it  be  given  ;  for  the 
railways  are  the  property  of  the  State.  Is  it  to  be  expected  that 
any  country  can  fight  such  a  combination  as  that  without  adopt- 
ing, at  all  events,  something  of  their  methods,  or  without  study- 
ing their  methods,  and  without  combining  together,  if  not  to 
imitate  them,  at  all  events  to  thwart  them  ?  "  He  had  put  the 
second  aspect  of  the  case  in  a  leader  in  Nature ',  on  i2th  Novem- 
ber 1914.  He  would  quote  it.  Dealing  with  the  organisation 
of  a  German  chemical  business,  he  pointed  out  :  "  First,  the 
management  consists,  not  in  a  board  of  well-meaning  elderly 
gentlemen  with  a  works-manager  in  their  employment,  but  in  a 
board  of  specialists,  whose  business  in  life  is  to  manage  the  factory 
financially,  chemically,  and  as  engineers,  and  who  are  very  highly 
paid  for  their  services.  Second,  these  gentlemen  and  a  special  staff 
are  continuously  on  the  look-out  for  any  scientific  discovery  or 
invention  which  can  prove  of  advantage  to  their  business.  Third, 
a  very  large  staff  of  men,  trained  in  universities  or  technical 
schools,  is  turned  on  to  the  problem  of  making  such  a  discovery 


330         THE   BRITISH   COAL-TAR   INDUSTRY 

commercial,  whether  by  securing  cheap  raw  material,  cheapening 
the  process  of  manufacture,  or  creating  a  public  demand  for  the 
article  to  be  manufactured.  Fourth,  a  legal  staff  is  maintained, 
whose  business  it  is  to  protect  by  patent  all  improvements, 
however  apparently  trivial,  and  to  describe  them  so  vaguely  as 
to  conceal  them  from  their  competitors  ;  these  gentlemen,  in 
some  cases,  have  also  to  advise  whether  piracy  is  likely  to  be 
successful  :  whether  it  may  not  be  possible,  by  infringing  a 
patent,  so  to  saddle  an  opponent  with  legal  expenses  as  to  break 
his  competition.  Fifth,  such  companies  are  so  powerful  that 
they  can  influence  the  central  Government  to  protect  all  new 
developments,  whether  by  imposing  duties  on  articles  which 
might  possibly  compete,  by  extending  bounties  to  exported 
products,  or  by  securing  advantages  in  freights  to  the  coast,  and 
in  shipping  the  goods  abroad.  Sixth,  agencies  are  maintained  all 
over  the  world  whereby  the  article  is  introduced  to  the  notice  of 
foreign  purchasers  ;  and  last,  an  extensive  credit  system  is 
encouraged."  German  competition  was  thoroughly  organised 
and  systematic  ;  their  plan  had  been  to  attack  some  material 
manufactured  here,  and,  by  one  of  the  means  alluded  to,  to  render 
its  manufacture  unprofitable.  Having  obtained  a  monopoly,  prices 
were  raised.  That  was  a  not  unusual  method  of  commercial 
warfare  ;  but  it  was  only  in  Germany  that  all  the  resources  of 
the  State  were  combined  to  render  it  easy.  How  were  such 
tactics  to  be  met  ?  First  of  all,  there  must  be  co-operation  and 
trust  among  our  chemical  manufacturers.  They  had  to  be  taught 
to  fight,  not  each  for  his  own  hand,  but  against  a  common  enemy. 
Smaller  works,  which  had  not  funds  to  maintain  an  expensive 
research  staff,  must  combine  to  obtain  efficient  laboratories.  The 
products  of  one  works  must  supplement  those  of  another,  and 
the  manufacturers  must  be  organised.  Second,  competition  which 
was  unfavourable,  owing  to  fiscal  regulations  or  patent  laws,  must 
be  combated  by  the  action  of  the  State,  after  advice  and  careful 
consideration,  so  that  our  manufactures  and  trade  might  not 
be  unfairly  attacked  by  duties,  by  export  bounties,  or  by  easy 
freights. 

Professor  JAMES  J.  DOBBIE  thought  it  might  confidently  be 
said,  with  regard  to  the  supply  of  trained  chemists,  that  at  present 
this  country  was  in  a  better  position  than  ever  it  had  been  before. 
In  the  smallest  of  the  Scottish  universities,  owing  in  the  first 
place  to  the  munificence  of  a  former  professor,  and  more  recently 


\ 

THE   SUPPLY   OF   CHEMICALS   TO   BRITAIN     331 

owing  to  the  operation  of  the  Carnegie  benefaction,  a  research 
laboratory  had  been  founded  and  endowed,  which  was  now  well 
able  to  hold  its  own  with  any  laboratory  in  this  country,  and  with 
many  of  the  German  laboratories.  At  present  there  were  no  less 
than  twelve  students  there,  all  of  whom  were  in  a  position  to  take 
part  in  work  to  which  they  had  been  invited  by  a  committee  of 
the  Royal  Society,  namely,  assisting  in  the  production  of  certain 
drugs  which  were  necessary  for  the  Army  and  Navy,  and  which 
at  present  could  not  be  had  from  the  ordinary  sources  of  supply. 
He  thought  that  was  an  encouraging  circumstance.  As  to  the 
capital,  no  one  would  doubt  that  that  would  be  forthcoming  if  it 
were  to  be  employed  for  the  particular  purposes  of  developing 
the  chemical  industries  which  had  hitherto  been  in  the  hands  of 
the  Germans.  But  there  remained  the  further  point  :  Were  the 
chemical  manufacturers  themselves  ready  to  employ  the  scientific 
assistance  which  was  needed,  and  were  they  ready  to  remunerate  it 
adequately  ?  Unless  they  recognised  the  necessity  for  the  em- 
ployment of  the  highest  science  in  the  development  of  their 
industries  very  little  progress  could  be  made.  It  was  to  the 
education  of  the  masters  of  the  industry  that  attention  had  to  be 
devoted.  He  was  glad  the  author  had  called  attention  to  the 
fact  that  this  country  had  contributed  some  of  the  great  funda- 
mental principles  to  chemistry.  There  was  no  want  of  originality 
in  this  country  ;  there  was  no  want  of  initiative  ;  where  we  had 
got  behind  was  simply  in  the  power  of  organisation,  or  rather  the 
failure  to  organise. 

Mr  A.  E.  BERRY  said  that  manufacturers  had  not  always 
received  the  assistance  and  help  which,  in  his  opinion,  should 
have  been  afforded  to  them.  A  few  days  ago  one  of  the  com- 
panies in  which  he  was  interested  received  an  inquiry  for  a  certain 
product  that  had  always  been  made  in  Germany.  That  product 
required  pure  duty-free  spirit.  His  company  wrote  to  the  Inland 
Revenue,  saying  they  had  accepted  the  business  and  must  have 
duty-free  spirit.  That  day  he  had  received  a  visit  from  an  officer 
of  that  department,  who  had  spent  an  hour  and  a  half  arguing 
that  the  product  must  be  made  by  something  else  than  duty-free 
spirit.  He  claimed  that  manufacturers  in  this  country  had  the 
knowledge  and  scientific  ability  to  manufacture  such  a  product, 
but  were  debarred  from  doing  so  by  the  Government  restrictions 
with  regard  to  duty-free  spirit. 

Professor  A.  G.  GREEN  remarked  that  the  question,  as  the 


332         THE   BRITISH    COAL-TAR    INDUSTRY 

author  stated,  was  simply  one  of  knowledge.  The  Germans  had 
considered  it  was  worth  their  while  to  pay  in  order  to  obtain 
knowledge  ;  we  had  not,  and  until  we  had  changed  our  methods 
we  should  still  continue  in  the  same  old  way.  An  instance  had 
come  under  his  notice  a  few  days  previously  which  showed  the 
manner  in  which  we  were  accustomed  to  proceed  in  this  country. 
A  certain  firm  in  the  North  of  England,  of  very  considerable 
standing,  had  their  attention  directed  to  a  certain  substance,  and 
were  advised  it  would  be  a  very  profitable  thing  to  take  up. 
Instead  of  making  inquiries  as  to  where  they  would  obtain  the 
best  scientific  skill  and  advice  as  to  the  manufacture  of  it,  or 
instead  of  engaging  a  chemist,  they  advertised  for  a  workman  who 
had  made  the  product.  They  succeeded  in  getting  a  workman, 
and  the  man  then  immediately  said  he  must  have  a  certain  raw 
material.  It  was  not  to  be  obtained.  Then  they  had  to  consider 
the  question  of  manufacturing  the  raw  material.  They  then 
proceeded  to  advertise  for  another  workman  with  a  knowledge 
of  its  manufacture.  He  (the  speaker)  did  not  know  the  sequel, 
but  he  thought  it  was  pretty  clear  what  it  would  be.  Sir  William 
Tilden  considered  there  were  no  difficulties  with  regard  to  indus- 
trial alcohol  at  the  present  time.  He  (the  speaker)  was  of  that 
opinion  until  a  month  or  two  ago,  but  from  inquiries  he  had 
made  he  was  no  longer  of  that  opinion.  The  law  as  it  stood 
would,  he  thought,  if  interpreted  in  a  liberal  manner,  suffice  to 
give  all  that  was  required,  but  as  the  law  was  now  interpreted  it 
did  not.  For  instance,  the  price  of  ether  in  England  was  nearly 
three  times  as  much  as  it  was  in  Germany.  That  simply  excluded 
the  manufacture  in  England  of  a  large  number  of  materials  in 
which  ether  was  required.  The  Excise  authorities  absolutely 
refused  to  allow  ether  to  be  made  from  pure  alcohol  ;  it  had  to 
be  made  from  industrial  alcohol.  That  put  a  large  extra  cost  on 
the  manufacture  of  ether  from  several  points  of  view.  Acetic 
ether  was  another  product  which  was  debarred  from  being  made 
from  pure  alcohol,  because  the  Revenue  people  considered  it 
would  be  possible  to  regenerate  alcohol  from  the  acetic  ether  ! 
Ether  was  the  starting-point  of  the  manufacture  of  quite  a 
number  of  fast  yellow  dyestuffs,  which  it  was  impossible  to  make 
in  this  country  owing  to  the  fact  he  had  just  stated.  But  he  did 
not  mean  to  say  that  the  alcohol  question  was  one  of  premier 
importance.  The  question  of  the  employment  of  chemists  came 
first.  The  British  manufacturer  must  employ  a  larger  number 


THE   SUPPLY   OF   CHEMICALS   TO   BRITAIN     333 

of  chemists,  and  he  must  reward  those  chemists  sufficiently  to 
make  it  worth  their  while  to  do  their  utmost. 

Mr  A.  CHASTON  CHAPMAN  said  that  there  was  a  very  large 
body  of  British  manufacturers  who  imagined  that  the  office  was 
the  central  and  most  important  part  of  their  works,  and  that  all 
they  had  to  do  was,  that  if  they  paid  their  chemists  (if  they 
employed  scientific  assistance  at  all)  £100  per  annum,  to  ensure 
that  at  the  end  of  the  year  there  was  £150  in  their  till.  It 
seemed  to  him  that  not  only  that  section  of  the  British  manu- 
facturers had  to  be  educated,  but  also  the  British  public,  who  in 
such  matters  were  exceedingly  ignorant ;  and  it  was  through  the 
British  public  that  pressure  could  be  brought  to  bear  on  the 
authorities — where  pressure  was  very  badly  needed. 

Mr  WALTER  F.  REID  remarked  that  he  did  not  grudge  the 
Germans  the  slightest  bit  of  profit  they  made  out  of  their  own 
inventions,  but  when  an  invention  was  made  in  this  country  and 
it  had  to  go  abroad  to  be  worked,  there  was  something  radically 
wrong  in  the  way  the  British  inventor  was  treated.  He  could 
give  dozens  of  instances  where  inventors  had  produced  good 
ideas,  but,  owing  to  lack  of  help  and  opportunity,  had  had  to  let 
their  ideas  die  or  sell  them  for  a  mere  song.  That  was  not  a 
healthy  state  of  things.  He  might  mention  that  he  invented 
smokeless  powder.  In  the  first  place  he  had  taken  it  to  a 
Government  factory,  and  explained  its  properties.  Some  time 
after  an  official  waited  upon  him  and  said  that  all  he  claimed  for 
the  powder  had  been  proved,  but  that  it  could  not  be  introduced 
into  the  Army  because,  if  it  was,  all  the  rifles  would  have  to  be 
altered  ! 

The  Government  should  assist  inventors.  British  manu- 
facturers were  in  the  position  of  an  untrained  mob  going  against 
a  drilled  army.  The  commercial  aspect  of  the  matter  was,  in  his 
opinion,  of  the  greatest  importance,  but  the  author  in  his  paper 
had  put  the  business  man  last.  He  (the  speaker)  ventured  to 
suggest  that  some  of  the  largest  and  best  industries  in  the 
country  had  been  developed  in  the  first  instance  by  good  men 
of  business. 

Colonel  CHARLES  E.  CASSAL  (President  of  the  Institution  of 
Chemical  Technologists)  said  plenty  of  trained  scientific  chemists 
were  certainly  necessary,  but  it  was  forgotten  that  in  order  to 
produce  the  trained  scientific  chemist  a  long  period  of  technical 
education  was  necessary,  which  put  a  very  severe  tax  upon  the 


334         THE   BRITISH   COAL-TAR   INDUSTRY 

father  of  the  young  chemist.  After  that,  he  had  to  be  offered 
something  which  was  worth  his  while,  and  which  would  attract 
the  right  sort  of  man.  Many  manufacturers  in  this  country 
had  followed  the  objectionable  practice  of  appointing  Germans 
as  their  chemists  in  preference  to  Englishmen,  because  the 
former  were  "  cheaper."  He  hoped  that  an  end  would  be  put 
to  this. 


XXV.:    1914 

BRITAIN  AND   GERMANY  IN   RELATION   TO 
THE  CHEMICAL  TRADE 

BY  WILLIAM  R.  ORMANDY,  D.Sc.,  F.C.A. 

(Journal  of  the  Royal  Society  of  Arts^  4th  December  1914,  p.  46) 

THE  fact  that  Germany  has  slowly  but  surely  been  gaining 
control  of  the  greater  part  of  the  chemical  industries  of  the 
world  has  been  brought  home  to  this  country  times  innumerable 
during  the  last  forty  years.  It  is  true  that  this  control  has  not 
extended  to  the  manufacture  of  what  are  known  as  heavy 
chemicals,  where  questions  as  to  the  cost  of  raw  materials,  fuel, 
and  freight  are  of  deciding  importance.  The  present  unhappy 
state  of  Europe,  causing  a  shortage  of  many  drugs  and  chemicals, 
has  brought  this  control  home  in  an  unmistakable  way  to  the 
public,  who  have  been  made  to  realise  what  the  manufacturers 
have  known  and  ignored  for  at  least  a  generation. 

It  is  probable  that  the  laws  relating  to  the  influence  of  en- 
vironment, which  have  been  proved  to  be  so  important  in  the 
animal  and  vegetable  world,  will  be  equally  applicable  to  the 
development  of  industries,  save  that  influences,  such  as  national 
temperament,  education,  and  financial  relations  of  a  complex 
nature,  have  to  be  brought  into  consideration.  Industrial 
development  on  a  very  large  scale  was  first  rendered  possible 
by  the  introduction  of  the  steam-engine  as  a  power  generator 
and  the  provision  of  adequate  means  of  transport.  At  a  period 
during  which  this  development  was  taking  place  here,  the  rest 
of  Europe  was  in  a  sufficiently  unsettled  state  to  permit  of  this 
country,  without  serious  opposition,  becoming  the  workshop  of 
the  world.  No  finesse  was  required  to  sell  the  output  of  our 
mills  and  our  ironworks.  America,  like  a  healthy  growing  child, 

335 


336         THE   BRITISH   COAL-TAR   INDUSTRY 

had  an  inconceivable  appetite  for  all  those  finished  and  inter- 
mediate  products  which   could   only  be  produced  by  a  nation 
whose  industries  had  been  slowly  developed  and  well  established. 
In  those  days  the  English  manufacturers,  who  paid  low  wages 
and  exacted  long  hours,  made  enormous  profits.     The  experi- 
menting which  had  to  be  done  to  develop  the  various  industries 
was  of   a    rule-of-thumb  character  and  essentially  non-scientific 
in  its  nature.     Probably  no  nation  is  so  well  fitted  as  the  Anglo- 
Saxon  race  to  develop  rapidly  along  such  lines.     As  a  race  our 
people    are   practically   inclined,    and   so   long   as    development 
required  nothing  more  than  the  close  application  of   a  healthy 
common  sense,  progress  was  astonishingly  rapid.     A   very  old 
man,  whose  family  was  one  of  the  earliest  to  take  up  the  manu- 
facture of  cast  steel  in  this  country,  has  told  me  that  in  the 
early  days  of  the  firm's  history  it  was  no  uncommon  thing  to 
receive  orders  for  tons  of  steel  required  for  the  manufacture  of 
drills  and  tools  to  open  up  the   virgin  wealth  of   America,  in 
which  not  only  was  no  price  mentioned,  but  it  was  explicitly 
stated  that  within  the  bounds  of  reason  quick  delivery  would 
compensate  for  any  price.     The  products  of   our  boiler  yards 
were  famed  throughout  the  world,  and  incredible  profits  were 
made  by  firms  whose  successors  have  found  the  competition  of 
recent  years  more  than  they  could  support.     This  was,  of  course, 
due  to  the  fact  that  in  the  days  of  prosperity  the  profits  were 
divided  to  the  last  penny,  the  machinery  was  allowed  to  get  out 
of  date,  and  the  working  people  refused  any  longer  to  play  the 
part  assigned  to  them  by  the  manufacturer  in  his  profit-making 
schemes.     Dr    Mollwo   Perkin  has  probably  given  the  correct 
explanation    for   this   pronounced   tendency   of    British    manu- 
facturers   to  starve  and  bleed   their  own  business.     The  rapid 
industrial  development  of  foreign  countries  called  for  enormous 
capital   for   railways,    shipping,    docks,  and   harbours,   and   the 
opening  up    of   mining  and  agricultural  properties,  and  it  was 
felt  that  a  better  return  could  be  obtained  from  such  ventures. 
English  spinners  and  weavers  were  supplying  the  whole  world 
with    their   products,  while  loom  and  mule  machinery  makers 
were  working  day  and  night  to  supply  these  foreign  purchasers 
with  the  machinery  for  their  infant  industries  which  were  in  future 
years   to   compete   with   the    home  country  for  their  own  and 
neutral  markets.     For  close  upon  a  hundred  years  the  tide  flowed 
in  our  favour.     There   was  no  necessity  to  practise  economy. 


CHEMICAL  TRADE  IN  BRITAIN  AND  GERMANY  337 

Nature  had  been  lavish  with  our  raw  materials,  our  insular 
position  and  the  proximity  of  our  manufacturing  centres  to  the 
sea-board  gave  us  natural  advantages  which,  added  to  a  favour- 
able situation  in  international  relations,  rendered  the  growth  of 
our  material  success  inevitable.  To  the  thinking  mind,  it  was 
obvious  that  such  a  concatenation  of  favourable  circumstances 
could  not  continue  indefinitely.  We  provided  other  countries, 
at  great  profit  to  ourselves,  with  all  the  means  necessary  for 
competing  with  us  in  these  markets  in  which  we  had  hitherto 
enjoyed  a  practical  monopoly.  Our  own  works  were  frequently 
equipped  with  out-of-date  machinery,  which  was  busily  employed 
in  making  more  modern  plant  which  was  put  into  the  hands  of 
those  who  realised  that  they  would  have  to  exert  their  powers 
to  the  utmost  if  they  were  to  gain  a  fair  share  in  the  barter  of 
the  great  international  bazaar.  The  British  industry  of  to-day 
is  in  the  position  of  a  son  inheriting  an  established  business,  and 
having  in  addition  a  very  large  income  derived  from  the  labours 
of  past  generations.  Properly  used,  such  a  situation  should 
make  for  enhanced  prosperity ;  but  even  such  powerful  ad- 
vantages may  be  nullified  if  the  effort  to  work  along  the  lines 
which  proved  successful  in  our  grandfathers'  days  be  continued 
too  long.  Capital  directed  by  ignorance  and  apathy  cannot  hope 
to  compete  for  ever  against  the  forces  which  are  brought  to  bear 
to-day. 

The  industrial  life  of  Germany  may  be  said  to  have  com- 
menced little  more  than  a  generation  ago.  To  all  intents  and 
purposes  an  inland  country,  with  little  sea-board,  they  were 
under  a  huge  disadvantage  in  every  department  which  required 
raw  materials  obtained  from  abroad.  In  many  directions  their 
natural  resources  were  comparatively  poor.  They  had  no  iron 
ores  which  were  comparable  with  the  hematites  of  Cumberland, 
their  limestone  was  largely  dolomitic,  their  coals  were  for  the 
most  part  poor  in  quality,  and  lay  often  in  distorted  seams,  more 
like  those  of  our  Bristol  coalfields  than  the  comparatively  easily 
worked  deposits  in  our  northern  area.  It  was  recognised  at  an 
early  period  in  their  industrial  development  that  national  progress 
in  a  country  situated  as  was  their  own  could  not  be  left  entirely 
to  individualistic  effort.  Nationalisation  of  railways  and  canals 
became  an  obvious  necessity  if  differential  traffic  rates  were  to 
be  allowed,  and  differential  rates  were  an  absolute  necessity  if 
large  industries  were  to  be  developed  in  the  interior  of  Germany 

22 


338         THE   BRITISH   COAL-TAR   INDUSTRY 

far  from  the  sea-board.  Too  much  credit  cannot  be  given  to 
the  far-sighted  way  in  which  every  problem  of  agriculture  and 
industry  in  Germany  is  regarded  from  a  national  standpoint. 
It  is  realised  by  everyone  that  individuality  must  be,  to  a'  certain 
extent,  fettered  for  the  benefit  of  the  nation  as  a  whole.  In  this 
country  individuality  runs  rampant,  and  except  in  times  of  stress, 
such  as  those  through  which  we  are  passing,  the  national  or 
Imperial  bearing  of  any  individualistic  action  receives  not  the 
slightest  consideration.  The  very  people  whose  fathers  sold 
land  to  the  railway  companies  at  absurdly  inflated  prices  now 
complain  that,  owing  to  the  high  railway  freights  in  this  country, 
they  cannot  make  adequate  profits  from  the  investment  of  the 
money  obtained  from  those  same  companies  by  an  earlier  ex- 
tortion. No  doubt  many  of  those  who  have  made  their  profits 
from  such  action  would  like  to  see  the  English  railways 
nationalised  and  freights  reduced  at  the  expense  of  that  patient 
beast  of  burden,  the  British  public.  Whereas  Germany  is  con- 
tinuously developing  her  network  of  waterways,  we  in  this 
country,  with  a  customary  lack  of  national  forethought,  allowed 
our  waterways  to  become  controlled  by  the  railway  companies. 

Having  thus  settled  the  enormously  important  question  of 
transport,  Germany  had  to  consider  the  lines  along  which  she 
should  seek  for  an  expression  of  her  industrial  destiny. 
Agriculture,  there  as  here  the  largest  individual  industry, 
received  attention  which  is  as  striking  as  is  the  lack  of  it  in  this 
country.  Proper  afforestation  schemes  were  rendered  compulsory  ; 
enormous  areas  of  land  fit  for  little  else  were  put  under  potato 
cultivation,  and  science  was  called  in  to  help  to  create  a  new 
outlet  for  the  crops.  Germany  became  essentially  the  starch-, 
glucose-,  and  alcohol-producing  country  of  Europe.  Other 
large  areas  were  used  for  the  cultivation  of  the  beet,  and  once 
again  science  was  called  in  to  assist  in  the  disposal  of  the  roots 
as  raw  materials  for  the  production  of  sugar.  If  the  manu- 
facturing of  iron  had  to  become  a  great  industry,  it  was  necessary 
to  develop  economic  methods  for  the  utilisation  of  the  great 
deposits  of  low-grade  phosphatic  iron  ores  which  were  those 
chiefly  available.  In  addition  to  the  home  deposits  of  iron  ore 
large  amounts  have  been  imported,  but  how  successfully  the 
problem  has  been  tackled  is  shown  when  we  consider  that 
twenty  years  ago  the  German  production  of  iron  was  a  mere 
fraction  of  our  own,  whereas  to-day  the  German  output  exceeds 


CHEMICAL  TRADE  IN  BRITAIN  AND  GERMANY  339 

the  British  by  nearly  100  per  cent.  The  problem  of  working 
up  the  complex  metallic  ores  has  fallen  almost  entirely  into 
German  hands.  They  alone  were  willing  to  spend  the  time 
and  money  necessary  on  researches  pertaining  thereto,  and  they 
alone  seemed  willing  to  devote  that  close  chemical  skill  and 
attention  which  is  necessary  in  dealing  with  these  complex 
problems.  In  the  early  days  of  the  chemical  industry  it  must 
have  been  quite  evident  that  Germany  could  not  hope  to  compete 
in  those  branches  of  heavy  chemicals  such  as  soda  ash,  caustic 
soda,  sulphuric  acid,  bichromate  of  soda,  alum,  etc.,  where  cheap 
raw  materials,  freights,  and  cheap  fuel  play  a  greater  r61e  than 
chemical  skill  and  complex  machinery.  There  is,  however,  not 
the  slightest  doubt  that  Germany  realised  years  ago  what  this 
country  has  not  yet  grasped — namely,  that  all  industrial  develop- 
ment tends  to  become  more  and  more  scientific.  The  adequate 
utilisation  of  the  by-products  from  an  industry  may  settle  the 
question  of  the  survival  of  the  industry  itself. 

The  necessity  for  broad  co-operation  in  great  industrial 
problems  was  recognised  and  acted  upon  in  Germany  in  a 
hundred  directions.  By-product  recovery  coke  ovens  were 
installed  in  the  immediate  neighbourhood  of  the  blast  furnaces, 
and  the  surplus  gas  from  both  was  used  for  power  generation. 
The  steelworks  were  erected  in  the  immediate  vicinity  of  the 
blast  furnaces,  so  that  the  surplus  power  might  have  an  economic 
outlet.  Where  it  was  impossible  to  bring  the  steelworks  to  the 
vicinity  of  the  coke  ovens  and  the  blast  furnaces,  the  surplus 
energy  from  these  was  transmitted  far  and  wide  in  the  form 
of  high-tension  electric  current  sold  at  an  astonishingly  low 
price  and  thus  tempting  to  the  introduction  of  new  small 
industries  within  the  immediate  area.  The  by-product  recovery 
coke  ovens  were  required  to  another  end.  Slowly  but  surely 
Germany  had  been  developing  her  fine  chemical  industries, 
drugs,  and  dyes.  Many  of  these  manufactures  were  dependent 
for  their  raw  materials  on  products  only  obtainable  in  quantity 
from  this  country.  We  have  been  building  up  an  enormous 
industry,  not  only  in  the  spinning  and  weaving  of  cotton  and 
woollen  yarns  and  fabrics,  but  a  correspondingly  great  industry 
in  the  bleaching,  dyeing,  and  finishing  of  these  products.  This 
has  been  chiefly  developed  on  dyes  obtained  from  Germany, 
but  while  we  have  been  content  to  leave  ourselves  entirely  in 
the  hands  of  others,  the  Germans  have,  by  the  exercise  of 


340         THE   BRITISH   COAL-TAR   INDUSTRY 

scientific  skill  and  a  sensible  use  of  capital,  rendered  themselves 
independent  of  this  country.  German  capital  was  spent  like 
water  to  foster  the  development  of  by-product  coke  ovens  and 
in  the  development  of  the  allied  fireclay  trade  for  the  production 
of  suitable  apparatus,  to  the  end  that  fifteen  years  ago  practically 
the  whole  of  the  hard  coke  produced  in  that  country  was  made 
to  give  up  its  toll  of  by-products  which  were  the  raw  materials 
for  their  great  chemical  industry. 

At  a  recent  meeting  of  the  Society  of  Chemical  Industry, 
Professor  Henderson  referred  to  the  chemical  industries  of 
Germany  as  being  merely  the  development  of  the  crumbs  from 
the  British  loaf  with  which  they  had  had  to  content  themselves. 
In  so  far  as  the  metallurgical  industries  are  of  necessity  chemical 
industries,  the  term  "  crumb,"  as  applied  to  an  iron  and  steel 
trade  much  greater  than  our  own,  seems  out  of  place,  and  the 
remark  is  only  another  unfortunate  example  of  the  willingness 
that  exists  in  many  quarters  to  pander  to  an  already  too  strongly 
developed  feeling  of  national  self-esteem.  The  British  as  a 
nation  never  show  up  so  favourably  as  when  they  are  placed  face 
to  face  with  difficulty.  As  a  race  we  have  so  much  of  which  we 
can  be  genuinely  proud  that  it  is  a  little  less  than  treason  when 
those  to  whom  the  people  should  look  for  guidance  and  warning 
feed  them  with  fulsome  flattery  and  lull  them  to  continued  sleep 
with  mental  opiates.  In  ever-increasing  degree,  both  in  this 
country  and  Germany,  the  population  are  dependent  on  in- 
dustries for  their  livelihood.  Both  countries  have  long  passed 
the  stage  at  which  their  home  market  is  capable  of  keeping  the 
industrial  machine  in  full  activity.  In  addition  to  each  being  the 
other's  largest  customer,  both  have  to  look  to  the  rest  of  the  de- 
veloped parts  of  the  world  for  an  additional  outlet.  Someone  has 
said  that  a  nation  gets  the  newspapers  it  deserves.  Judging  by 
what  has  appeared  in  some  portions  of  the  daily  Press  during 
recent  months  upon  the  subject  of  German  trade,  it  is  devoutly  to 
be  hoped  that  the  common  sense  of  the  British  nation  will  not  be 
judged  thereby.  During  the  past  ten  years  a  nation  of  over  sixty 
millions  has  been  increasingly  occupied  in  industrial  operations. 
Our  own  smaller  population  has,  on  the  whole,  been  equally 
fully  employed  during  the  same  period,  and  yet  people  write 
as  though  there  was  a  possibility  that  a  large  proportion  of  the 
activities  of  the  larger  nation  could  be  profitably  undertaken  in 
the  smaller  country  whose  work-people  have  been  for  the  most 


CHEMICAL  TRADE  IN  BRITAIN  AND  GERMANY  341 

part  well  and  profitably  employed  for  the  last  decade.  The 
absurdity  of  this  requires  no  refutation.  Indignation  is  expressed 
at  the  discovery  that  German  people  and  German  capital  are  by 
way  of  controlling  an  ever-growing  number  of  industries  in  this 
country.  I  have  not  seen  that  any  serious  attempt  has  been 
made  to  the  much  more  serious  end  of  discovering  why  the 
Germans  should  desire  or  should  be  able  to  get  such  a  foothold 
in  this  country.  In  some  few  instances  I  could  supply  an 
answer  from  my  own  experience.  We  have  already  seen  how 
the  German  Government  brings  science  and  agriculture  to  work 
together  in  afforestation,  and  the  cultivation  and  utilisation  of 
potatoes  and  beetroots,  but  throughout  the  German  national 
history  the  Government  has  recognised  that,  as  a  people,  they 
are  in  ever-growing  degree  forced  to  live  on  industry,  and  that 
modern  industry  is  built  on  the  hand-in-hand  co-operation  of 
science  and  capital.  This  country  is  dependent  upon  industrial 
development  for  its  very  existence  in  a  higher  degree  than 
Germany,  and  yet  so  far  as  governmental  assistance  or  interest 
is  concerned  the  principal  occupation  of  the  British  people  might 
be  the  signing  of  dividend  coupons.  The  German  Government 
is  incomparably  poorer  than  our  own,  and  yet  the  financial 
assistance  which  it  renders  to  technical  education  is  immeasur- 
ably greater.  The  standard  of  general  education  is  undoubtedly 
higher,  no  doubt  largely  in  consequence  of  the  temptation 
offered  by  their  one-year  service  system  in  the  army  to  those 
who  have  passed  a  certain  high  standard  of  efficiency.  In  a 
land  where  the  standard  of  payments  is,  on  the  whole,  much 
lower  than  our  own,  the  leading  men  of  German  technical  schools 
are  far  better  paid  than  in  this  country.  The  heads  of  the 
technical  school  staffs  are  encouraged  to  become  acquainted  with 
the  latest  technical  progress.  It  is  fully  realised  that  a  purely 
academic  teacher  cannot  turn  out  first-class  technical  men.  The 
technical  industries  instantly  claim,  at  higher  salary,  the  members 
of  the  staff  of  technical  colleges  who  have  carried  out  original 
investigations  which  seem  likely  to  open  out  industrial  possi- 
bilities, and  it  is  not  an  uncommon  thing  for  such  a  man  to  be 
reclaimed  by  some  technical  institution  at  a  later  date  at  a  still 
higher  salary.  It  is  realised  that  the  right  man,  who  has  works 
experience  as  well  as  technical  knowledge,  is  worth  far  more 
to  the  nation  as  a  teacher  than  in  a  private  capacity.  If  an 
industry  requires  to  make  use  of  ingredients  such  as  alcohol  and 


342         THE   BRITISH   COAL-TAR   INDUSTRY 

ether,  which  are  under  excise  control,  the  Government  will  go  to 
the  greatest  trouble  to  arrange  matters  in  such  wise  that  no  needless 
restraint  is  imposed.  That  the  staff  of  a  Government  department 
should  interpret  a  Government  order  in  an  unduly  restrictive 
sense,  so  that  an  industry  might  thereby  be  hampered,  is  there 
inconceivable.  Only  in  Great  Britain  and  Turkey  are  Govern- 
ment restrictions  allowed  to  be  interpreted  at  the  will  of  the 
permanent  officials.  I  do  not  for  one  moment  wish  to  imply 
that  I  consider  that  the  question  of  industrial  alcohol  has  been 
of  the  main,  or  even  of  serious,  import,  compared  with  others, 
in  our  neglect  of  the  fine  chemical  industries.  I  quote  it  rather 
as  an  example  of  the  contemptuous  attitude  which  our  Govern- 
ment has  hitherto  adopted  towards  matters  industrial.  In  certain 
branches  of  the  chemical  trade  it  is  essential  to  have  the 
chemically  pure  alcohols  and  ethers,  but  the  would-be  manu- 
facturer is  told,  by  the  Government,  in  effect,  that  he  is  not  to 
be  a  judge  of  what  is  necessary,  but  that  the  question  will  be 
settled  by  some  heaven-sent  genius  in  their  permanent  employ 
who,  like  the  journalist  on  a  halfpenny  paper,  knows  more  about 
the  subject  than  the  man  who  has  made  it  a  life's-work. 

A  feature  of  the  German  industries  is  their  willingness  and 
ability  to  work  in  co-operation,  as  is  shown  in  many  ways  which 
are  no  doubt  familiar  to  most  of  you,  but  with  which  we  have 
not  time  to  deal.  With  all  the  help  which  a  favourably-inclined 
government  could  render,  the  German  industries  would  have 
been  unable  to  approach  their  present  standard  of  efficiency  had 
it  not  been  for  the  remarkable  co-operation  which  takes  place 
between  science  and  capital.  This  can  perhaps  be  best  illustrated 
by  means  of  some  concrete  examples.  Let  us  suppose  that  some 
chemist  in  Germany  has  discovered  a  new  and  cheaper  method 
for  making  some  chemical  product  which  is  in  considerable  de- 
mand, or  which  might  become  a  large  article  of  manufacture  if 
the  price  were  sufficiently  low.  If  the  manufacture  is  likely  to 
require  a  considerable  capital,  the  inventor  would  probably  go  to 
one  of  the  large  banks.  The  German  banks  permanently  retain 
the  services  of  some  of  the  leading  authorities  on  a  wide  range  of 
subjects,  and  the  inventor  would  be  asked  to  put  all  his  case  before 
the  particular  expert  in  charge  of  his  department.  If  the  report 
were  of  a  sufficiently  satisfactory  nature  on  the  scientific  side,  the 
bank  would  proceed  to  make  their  own  inquiries,  through  the 
many  channels  open  to  them,  as  to  the  probable  outlet  for  the 


CHEMICAL  TRADE  IN  BRITAIN  AND  GERMANY  343 

new  product.  If  the  outlook  were  in  all  respects  sufficiently 
satisfactory,  they  would  advance  the  necessary  capital  at  a  reason- 
able rate  of  interest,  making  certain  stipulations  such  as  that  the 
business  should  be  carried  through  their  bank  ;  that  payment  for 
the  finished  products  should  be  made  through  the  bank  ;  that  no 
contract  for  the  sale  of  the  finished  product  should  be  made  with 
any  firm  without  their  consent.  The  bank  having  much  greater 
facilities  for  gauging  the  financial  standing  of  the  purchasing 
public,  in  this  wise  protect  their  own  interests  and  that  of  the 
inventor. 

Again,  nothing  is  more  startling  to  the  Englishman  than  the 
ease  with  which  one  can  gain  admission  to  those  in  command  of 
the  great  industries.  The  directors  of  the  German  companies, 
for  the  most  part,  and  the  managing  director  invariably,  are  men 
of  high  technical  skill  in  the  business  they  control.  The  idea  of 
putting  a  stockbroker  or  a  retired  army  colonel  at  the  head  of  a 
scientific  industrial  concern  would  be  regarded  as  an  act  of  mad- 
ness. Not  only  are  German  businesses  run  by  men  who  under- 
stand them,  but  these  industrial  leaders  have  always  time  to  give 
adequate  consideration  to  any  new  proposal  which  is  brought 
before  them.  It  would  be  the  exception  rather  than  the  rule  to 
find  directors  in  an  English  company  who  were  capable  of  ap- 
preciating, still  less  of  judging,  the  merit  of  a  technical  point 
relating  to  their  own  business.  It  would  be  almost  an  impossi- 
bility for  an  unknown  outsider  to  obtain  admission  to  such 
directors,  and  even  if  the  unknown  inventor  succeeded  in  getting 
within  the  veil  which  hides  the  holy  of  holies,  it  would  probably 
be  to  find  that  the  master-mind  had  so  many  appointments  that 
he  never  by  any  chance  had  time  enough  to  consider  any  proposal 
thoroughly.  The  heads  of  a  German  concern  have  always  time 
to  look  thoroughly  into  anything  which  interests  them  ;  they  are 
sufficiently  technical  to  realise  the  necessity  for  going  into  details, 
a  works  experience  having  taught  them  that  it  is  on  details  that 
great  processes  come  to  grief.  In  spite  of  their  intellectual  and 
commercial  attainments,  however,  these  directors  are,  in  some 
respects,  both  modest  and  unassuming.  They  still  think  that 
success  can  be  purchased  only  at  the  cost  of  labour  ;  they  are 
content  to  work  from  8.30  to  6.30,  with  two  hours'  pause  in  the 
middle  of  the  day,  and  they  work  full  six  days  to  the  week.  No 
doubt  they  envy,  but  they  do  not  lay  claim  to,  that  super-type  of 
intellect  which,  labouring  hard  from  eleven  till  four  with  an  in- 


344         THE   BRITISH   COAL-TAR   INDUSTRY 

terval  for  rest,  sometimes  even  five  days  a  week,  expects,  not  only 
to  retain  its  old  position,  but  to  dispossess  its  competitors  ;  they 
even  learn  foreign  languages  so  that  they  may  profit  by  the 
knowledge  gained  by  other  people  in  other  countries. 

Let  us  suppose  for  one  moment  that  it  was  Germany  that 
was  short  of  drugs,  photographic  chemicals  and  dyes,  and  that 
England  had  possessed  a  monopoly  in  these  products.  Further, 
we  will  suppose  that  the  joint  general  manager  and  head  chemist 
of  one  of  the  large  English  drug  and  photographic  chemical 
works  had  found  himself  in  Germany  at  this  period,  with 
sufficient  acquaintances  in  that  country,  men  with  whom  he 
had  for  many  years  made  large  contracts  and  who  were  fully 
cognisant  of  his  scientific  and  technical  ability  to  guarantee  his 
claims.  He  could  go  to  any  bank  and  say  :  "  I  can  show  you 
how  to  make  a  number  of  photographic  chemicals  and  drugs 
even  more  cheaply  than  they  can  be  made  in  the  country  which 
has  hitherto  controlled  the  manufacture,  because  you  have  the 
necessary  raw  materials,  because  you  have,  indeed,  previously 
sold  these  raw  materials  to  the  previous  makers.  I  bring  you 
the  necessary  evidence  that  these  products  can  be  made  at  half 
the  sales  price  obtaining  before  the  war,  and  I  can  demonstrate 
that  the  sale  in  your  own  and  neutral  countries  of  these  products 
amounts  to  some  thousands  of  tons  per  annum,  and  that,  under 
normal  circumstances,  after  the  war  is  over,  it  will  be  impossible 
for  your  business  to  be  displaced  by  undercutting.  Finally,  I 
will  bring  you  reputable  dealers  who  will  make  contracts  for 
hundreds  of  tons  of  these  products  at  prices  which  will  pay  for 
the  plant  and  show  profits  in  one  year's  working."  The  bank 
would  confirm  these  statements  through  their  experts,  and  probably 
within  forty-eight  hours  all  the  money  that  was  required  would 
be  available  at  yj  per  cent.  The  man  who  possessed  the  scientific, 
technical,  and  commercial  knowledge  would  thus  be  enabled  to 
build  up  a  business  which  would  be  profitable  to  himself  and 
valuable  to  the  community,  the  fact  being  that  it  is  recog- 
nised in  Germany  that  capital  is  entitled  to  a  fair  return  and 
nothing  more. 

Now  let  us  imagine  that  circumstances  were  reversed.  It 
would  require  the  pencil  of  a  Hassall  adequately  to  depict  the 
scene  in  the  board-room  of  an  English  bank  where  such  a 
proposal  had  been  made.  One  can  imagine  the  possessor  of 
such  knowledge  offering  it  to  existing  chemical  works. 


CHEMICAL  TRADE  IN  BRITAIN  AND  GERMANY  345 

Modern  commerce  is  warfare,  and  the  weapons  employed  are 
inventions,  tireless  industry,  skill,  and  capital.  We  make  the 
mistake  of  putting  the  last  first.  Those  who  do  research  and 
make  inventions,  whether  in  chemistry,  engineering,  or  any  other 
branch,  are  the  yeast  which  leaven  the  whole  mass,  but  in  this 
country  we  do  not  allow  those  conditions  of  warmth  which  permit 
the  yeast  to  work.  Gold  in  itself  is  not  nearly  so  valuable  a 
metal  as  iron,  and  we  are  slowly  but  surely  finding  out  that 
capital  itself  is  an  over-valued  possession  if  it  be  not  used  for 
the  benefit  of  the  industries  and  consequently  of  the  nation  as 
a  whole. 

DISCUSSION 

The  Right  Hon.  Lord-Justice  MOULTON  said  that  he  had 
had  allotted  to  him  for  several  weeks  past  the  business  of  in- 
vestigating into  the  question  of  the  supplies  of  articles  which  in 
peace  time  were  imported  from  Germany.  First  and  foremost 
of  those  had  been  the  problem  of  the  great  chemical  trades, 
especially  the  great  industry  in  synthetic  dyes,  and  he  had  had 
an  opportunity  of  marking  in  detail  those  things  in  which  England 
had  allowed  herself  to  be  supplied  in  chemicals  from  Germany. 
He  could  assure  the  audience  that  he  had  noted  the  fact  with 
great  sadness,  and,  he  was  bound  to  say,  it  was  a  great  national 
humiliation.  The  fact  was  that  chemistry  opened  up,  especially 
some  fifty  years  ago,  a  domain  of  industrial  wealth  which  he 
could  only  compare  to  the  domain  which  was  opened  up  when 
steam  power  was  first  invented  ;  and  to  his  great  sorrow  he 
could  come  to  no  conclusion  but  one,  and  that  was,  that  either 
from  being  too  well  off,  or  from  sluggishness  of  intellect,  or  from 
the  fact  that  the  capital  of  the  country  had  passed  into  the  hands 
of  people  who  were  unwilling  either  to  learn  or  to  think,  England 
had  abstained  almost  entirely  from  attempting  to  reap  the  rich 
harvest  that  was  opened  to  the  industrial  world  by  the  advances 
in  organic  chemistry.  The  fact  was  too  well  marked  for  us  to 
pass  it  by  as  being  a  mere  incident  in  national  life.  Of  course, 
no  one  thought  that  every  nation  could  do  everything  ;  and  that 
nations  should,  to  a  certain  extent,  specialise,  should  take  ad- 
vantage of  their  natural  position,  and  the  deposits  that  they 
found  in  their  land,  their  climate,  and  things  of  that  kind,  was 
not  only  normal  but  desirable.  But  thought  depended  on  no 
climate.  Thought  was  open  to  us  all  ;  and  the  fact  that  England 


346         THE   BRITISH   COAL-TAR   INDUSTRY 

neglected  the  chemical  industries  could  not  be  explained  away 
by  any  suggestion  that  it  was  either  incapable  or  for  any  natural 
reason  unfitted  for  their  pursuit.  One  had  to  look  deeper  than 
that.  One  had  to  find  some  fault  either  in  the  national  character 
or  in  the  national  behaviour  which  would  account  for  it  ;  and  he 
did  not  believe  that  England  could,  after  the  war,  survive  as  a 
great  industrial  nation  if  she  did  not  correct  that  fault,  if  she 
did  not  make  an  effort  to  take  her  place — and  that  an  uppermost 
place — in  the  world  of  industry  in  chemical  matters  as  well  as 
in  all  others.  If  the  conclusion  was  come  to  that  it  had  been 
by  a  national  fault  that  we  had  missed  it  in  the  past,  and  that 
we  were  not  going  to  live  a  disgraced  life  in  future,  it  meant 
that  that  fault  must  be  found  out  for  the  purpose  of  avoiding 
it,  and  there,  he  thought,  a  lesson  might  be  taken  from  our 
enemies.  To  his  mind  by  far  the  most  glorious  moment  in 
the  history  of  Prussia  was  not  the  moments  of  her  military 
successes — it  was  the  moment  of  her  deepest  disaster.  Those 
who  knew  Prussian  history  would  remember  that  after  the 
nation  had  been  prostrated  by  Napoleon  in  the  Battle  of  Jena 
the  national  independence  was  utterly  taken  away.  The  restric- 
tions the  conqueror  put  upon  them  were  humiliating  in  every 
way.  At  that  time  there  arose  a  set  of  men,  of  whom  he  chose 
to  name,  first,  Fichte,  who  told  the  Prussian  people  in  the 
clearest  language  that  their  disaster  was  due  to  their  national 
faults,  and  pointed  out  the  way  that  they  must  correct  these  ;  and 
in  the  most  unsparing  language  he  told  them  that  it  was  only  by 
self-discipline,  only  by  taking  to  heart  their  disaster,  seeing  in  it 
the  natural  consequence  of  their  national  faults,  that  they  could 
possibly  get  the  resolution  or  the  strength  to  replace  their  nation 
in  the  position  which  it  ought  to  occupy.  The  whole  nation 
listened.  It  was  at  that  time  that  the  Germans  took  to  physical 
development  and  voluntary  drilling.  They  prepared  themselves 
in  every  possible  way  for  that  coming  fight  which  they  hoped 
they  would  have  with  their  oppressors,  and  which  they  had  in 
the  course  of  a  very  few  years,  but  they  did  it  under  the  exhorta- 
tions of  these  men,  because  they  did  not  attempt  to  hide  from 
themselves  that  it  was  the  nation  that  was  to  blame  for  its 
misfortunes. 

The  fact  that  our  chemical  industries  were  in  such  a  backward 
state,  with  certain  exceptions  of  those  which  needed  least  thought 
and  least  study  and  least  knowledge,  was  grave  enough,  if,  as 


CHEMICAL  TRADE  IN  BRITAIN  AND  GERMANY  347 

he  said,  it  was  due  to  our  national  faults — it  was  grave  enough 
for  us  in  these  days  to  rouse  ourselves  as  the  Prussians  did  rather 
more  than  one  hundred  years  ago.  He  was  quite  sure  that  if 
we  did  do  it  the  same  result  would  come — that  we  should  regain 
our  position,  and  regain  it  with  even  more  glory  than  it  possessed 
before.  There  was  a  time  when  in  no  industry  could  England 
look  on  other  nations  as  its  superior.  Now,  in  the  chemical 
industry — by  which  he  meant  mainly  the  organic  chemical  industry 
— it  was  all  but  insignificant,  and  he  read  with  very  bitter  feelings 
an  address  of  one  of  the  ablest  industrial  chemists  in  the  world, 
the  head  of  the  German  chemical  industry,  who  was  talking  about 
the  very  subject,  and  who  said  :  "  England  talks  now  of  not  only 
holding  her  own  in  war,  but  beating  us  in  our  chemical  industries. 
She  cannot  do  it,  and  that  is  because  the  nation  is  incapable  of 
the  moral  effort  to  take  up  an  industry  like  that — which  implies 
study,  which  implies  concentration,  which  implies  patience,  which 
implies  fixing  one's  eye  on  the  distant  consequences  and  not 
considering  merely  the  momentary  profit."  When  he  read  those 
words  he  asked  himself,  Was  that  not  a  fair  judgment  for  a 
foreigner  who  could  not  know  the  resources  of  the  English 
people  in  the  way  of  repentance  and  resolution  and  reformation  ? 
Was  it  not  fair  for  that  gentleman  to  say  that  our  behaviour 
during  all  these  years  showed  that  we  were  incapable  of  doing 
it  ?  And  he  would  tell  them  frankly,  that  if  we  did  not  take  the 
lesson  to  heart  at  the  time  of  this  war,  and  when  the  war  had 
passed — when,  as  we  believed,  we  should  have  severed  ourselves 
from  the  military  domination  of  Germany — resolve  to  save  our- 
selves from  industrial  domination,  all  he  could  say  was  that  the 
victory  of  Germany,  if  not  in  the  form  that  it  would  desire, 
would  be  quite  as  great  as  it  could  wish. 

Sir  WILLIAM  A.  TILDEN  said  he  had  listened  with  mixed  feel- 
ings not  only  to  the  paper  but  to  Lord  Moulton's  remarks.  He 
could  not  help  hoping  most  sincerely  that  the  words  which  had 
been  used  by  Lord  Moulton  would  find  an  echo  in  those  regions 
inhabited  by  the  leaders  of  British  industry  ;  for  it  appeared  to 
him  that  unless  a  good  many  of  them  first  of  all  were  brought 
to  acknowledge  their  position  of  humiliation,  and  secondly,  de- 
termined that  if  they  were  too  old  themselves  to  learn,  at  any 
rate  their  sons  and  successors  should  be  taught  what  was  neces- 
sary in  the  way  of  scientific  instruction  connected  with  their  own 
businesses,  then  it  was  all  over  with  British  industry.  He  must 


348         THE   BRITISH   COAL-TAR   INDUSTRY 

say  out  of  his  own  experience,  living  as  he  had  for  fourteen  years 
in  a  great  industrial  centre,  that  many  of  the  author's  pungent 
remarks  were  really  not  exaggerated.  He  used  to  see,  with  great 
regret,  young  men  driving  to  business  in  the  morning  at  eleven 
o'clock  when  the  works  had  been  going  from  six  o'clock.  In 
many  works  which  he  had  visited  he  invariably  was  amazed  at  the 
extraordinary  ignorance  displayed  on  the  part  of  the  partners  them- 
selves in  the  operations  which  they  were  supposed  to  conduct  in 
their  businesses.  Over  and  over  again  he  had  been  in  works  in 
the  Black  Country,  and  his  friend,  the  director  or  manager,  was 
exceedingly  anxious  to  show  him  anything  ;  but  if  he  asked  any 
question  about  details  the  manager  or  director  could  not  answer 
them,  but  sent  down  the  yard  for  "  Old  Tom  "  or  "  Old  George," 
who  was  the  only  person  in  the  place  who  seemed  to  know  how 
the  process  could  be  conducted.  He  did  not  believe  that  the 
serious  character  of  the  question  of  education  had  yet  been  com- 
pletely realised  by  the  present  industrial  directors  and  leaders, 
and  he  could  not  help  thinking  that  that  was  one  of  the  most 
important  considerations  to  be  taken  into  account  at  the  present 
time — that  the  young  men  who  were  to  be  the  manufacturers  of 
the  future  should  have  a  very  different  kind  of  career  from  that 
which  had  been  hitherto  prevalent. 

Dr  M.  O.  FORSTER  said,  whilst  fully  agreeing  with  the  author 
in  his  castigations  of  the  manufacturer  and  the  Government, 
yet  he  did  think  that  while  chemists  were  so  busy  in  casting 
motes  from  other  people's  eyes,  there  was  one  beam  in  their  own 
which  certainly  should  be  removed  forthwith,  and  he  thought 
the  present  opportunity  was  the  right  occasion  to  remove  it. 
They  had  too  long  allowed  confusion  in  the  public  mind  as 
to  what  really  chemistry  was,  and  what  chemists  did.  It  was 
perfectly  ridiculous  that  any  attempt  whatever  should  be  made 
to  capture  German  trade  while  the  general  public  had  not  the 
faintest  idea  of  the  difference  between  the  chemist  and  the  drug- 
gist. At  the  present  time  the  only  people  who  were  entitled  to 
call  themselves  chemists  were  those  who  had  undergone  a  course 
of  training  at  the  Pharmaceutical  Society  or  who  had  passed  ex- 
aminations conducted  by  that  body.  In  fact,  he  believed,  of  all 
the  chemists,  so-called,  present  that  evening,  only  Sir  William 
Tilden  was  entitled  to  call  himself  a  chemist  by  law.  In  Germany 
and  France  chemists  and  druggists  were  clearly  defined. 

Dr    RUDOLPH    MESSEL  thought   that   we   as    a    nation    had 


CHEMICAL  TRADE  IN  BRITAIN  AND  GERMANY  349 

been  blind,  so  far  as  new  chemical  industries  were  concerned. 
We  had  everything  ready  at  our  hand.  At  one  time  there  was 
a  great  deal  of  grumbling  about  education  in  science.  He  had 
been  in  England  for  forty-five  years,  and  he  could  well  speak 
about  the  enormous  progress  which  had  been  made  in  this 
country  as  far  as  chemistry  was  concerned.  There  was  talent 
enough,  capital  enough,  raw  material — everything.  But  what 
was  lacking  was  enterprise.  If  the  talent  which  was  now  avail- 
able in  this  country  was  utilised,  the  industry  would  do  just  as 
well  here  as  in  Germany.  He  had  to  give  one  word  of  warning 
in  establishing  new  industries — first  of  all  to  be  sure  that  we  only 
took  up  those  industries  which  we  were  prepared  to  defend  when 
war  was  over. 

Dr  F.  G.  OGILVIE  said  that  the  deplorable  condition  to 
which  the  author  had  drawn  attention  was  not  at  all  peculiar  to 
the  chemical  industry  ;  it  has  been  observable  in  a  great  many 
other  industries.  There  had  been  a  tendency  in  connection  with 
many  individual  industries  for  the  divorce  of  the  control  of  capital 
from  the  knowledge  and  experience  required  to  apply  capital 
effectively.  It  arose  in  the  following  way — a  man  had  done  very 
well,  say,  in  the  manufacture  of  tweeds  in  a  centre  where  a  large 
tweed  industry  was  going  on.  His  family  found  themselves 
very  well  to  do,  and  were  attracted,  as  young  men,  much  more 
to  field  sports,  county  meetings,  and  things  of  that  sort  than  they 
were  to  the  serious  study  of  their  own  particular  business.  The 
net  result  was,  when  they  came  into  power  they  had  to  work  the 
business  by  managers,  often  underpaid  and  undertrained,  who 
naturally,  even  when  they  proved  themselves  very  good  men, 
had  not  the  ready  access  to  the  application  of  capital  year  in  and 
year  out  which  was  necessary  to  keep  the  business  up  to  date. 
This  did  not  happen  where  the  sons  had  added  scientific  training 
to  practical  experience  in  the  works.  In  that  case  there  were 
good,  solid,  steady-going  businesses  which  were  introducing  new 
products  just  as  fast  as  could  be  wished. 

Mr  ADAIR  ROBERTS  said  that  many  of  the  businesses  which 
it  was  now  sought  to  capture  from  Germany  could  be  started 
with  very  little  capital. 

Mr  WALTER  F.  REID  said  he  thought  it  was  quite  impossible 
to  suggest  that  a  young  chemist,  just  out  of  a  college  or  uni- 
versity, could  get  a  large  salary  unless  he  showed  himself  to  be 
worth  it.  An  employer  would  look  at  him  as  a  beginner  from 


350         THE   BRITISH   COAL-TAR   INDUSTRY 

the  industrial  point  of  view.  In  fact,  he  was  an  apprentice,  and 
if  he  was  not  willing  to  take  the  salary  of  an  apprentice  at  the 
beginning  he  could  not  grumble  at  the  capitalist,  who  opened  up 
to  him  a  very  good  future  of  great  promise.  With  regard  to  the 
glass  industry,  we  had  lost  that  industry  chiefly  through  the 
unwillingness  of  the  workers  in  the  trade  to  allow  apprentices  in 
sufficient  number.  After  the  production  of  capital,  the  next 
important  point  was  the  security  of  it.  He  could  not  put  the 
matter  more  clearly  than  it  was  put  by  the  Institute  of  Chemistry, 
which  said,  "  Provided  that  the  manufacturers  could  be  afforded 
some  guarantee  of  permanency  for  their  enterprise,  and  that  they 
may  have  some  reasonable  assurance  that  at  the  conclusion  of  the 
war  the  newly  developed  industry  will  not  suffer  from  foreign 
competition,  hitherto  made  possible  by  economic  conditions 
which  do  not  prevail  in  this  country."  Dr  Messel  had  said 
exactly  the  same  thing.  If  the  capital  which  would  have  to  be 
invested  in  new  and  expensive  plant  and  in  the  payment  of  re- 
search workers  and  other  workers  could  not  be  secured,  then  the 
capitalist  could  not  be  blamed  for  not  coming  forward.  Our 
workmen  and  capitalists  must  be  given  the  same  protection  as 
Germany  gave  to  theirs.  Our  German  competitors  could  then 
be  met  on  equal  terms,  and  he  was  not  afraid  in  the  least  what 
Englishmen  would  then  do. 

The  Lecturer  said  he  agreed  absolutely  with  Dr  Messel  that 
we  must  be  most  careful  to  take  up  only  those  industries  where 
we  were  at  least  on  as  good  a  footing  as  the  Germans  were  with 
regard  to  raw  material.  With  reference  to  workmen,  he  had  not 
the  slightest  doubt  that  English  workmen  were  better  than  any 
other  workmen  on  the  face  of  the  earth.  But  up  to  the  present 
neither  the  English  workman  nor  the  English  chemist  had  been 
given  half  a  chance  to  handle  modern  scientific  processes.  It 
was  the  opportunity  to  let  each  of  them  prove  what  he  could 
do  that  had  been  lacking. 

Mr  W.  H.  MAW  said  that  the  state  of  affairs  which  the  author 
had  described  as  existing  in  the  chemical  industry  also  existed  in 
past  times  in  many  other  industries.  In  the  case  of  the  engineer- 
ing trades  and  iron  and  steel  manufactures  the  last  twenty  years 
had  seen  a  very  remarkable  advance  in  the  recognition  of  the 
value  of  scientific  research,  and  he  hoped  the  same  advance  would 
take  place  in  the  chemical  industry. 


XXVI. : 

THE  MANUFACTURE  OF  ANILINE  DYES 
IN  ENGLAND 

BY  THE  RIGHT  HON.  LORD-JUSTICE  MOULTON, 
P. C.,  K.C.,  F.R.S. 

(Address  delivered  in  the  Town  Hall,  Manchester,  on  8th  Dec.  1914) 

SOME  weeks  ago  now  I  was  asked  by  Government  to  take  the 
Chairmanship  of  a  small  Committee  that  had  to  investigate  the 
straits  into  which  England  was  put  by  being  cut  off  from  that 
great  supplying  nation,  Germany.  I  have  had  to  investigate  all 
the  unsatisfied  wants  that  have  sprung  from  this  war,  and  I  am 
glad  to  say  that  in  almost  all  the  cases  which  cropped  up — so 
numerously  at  first — it  has  been  found  that  the  resources  of 
English  enterprise  were  sufficient  to  meet  the  demand  ;  that 
some  makers  have  been  more  attentive  to  the  variety  of  the 
tastes  of  their  customers  ;  that  others  have  increased  their  works  ; 
that  others  have  added  new  branches  to  their  business  ;  and  that 
the  straits  have  been  alleviated  if  not  removed.  Everything  that 
has  happened  has  placed  in  harsh  and  dissonant  contrast  the 
question  of  dyes.  Nothing  that  I  have  seen  during  these  weeks 
— and  I  can  claim  to  have  spent  almost  every  hour  of  the  day  in 
meeting  the  members  of  the  trades  affected,  and  in  trying  my  best 
to  find  some  way  out  of  the  difficulties — nothing  that  I  have  seen 
in  these  long  weeks  has  weakened,  nay,  I  can  say  nothing  has 
failed  to  strengthen,  my  feeling  of  the  gravity  of  this  problem. 

The  consequence  is  that  after  long  reflection  I  have  come 
to  certain  conclusions,  and  I  have  not  hesitated  to  place  them 
in  the  clearest  language  before  the  Government.  Now  the 
Government  has  taken  an  unusual  and  almost  unprecedented 
step  in  the  direction  to  which  I  refer.  I  am  not  responsible  for 


352         THE   BRITISH   COAL-TAR   INDUSTRY 

the  details  of  that  step.  I  am  not  in  any  way  connected  with  the 
shape  or  form  in  which  the  action  is  to  take  place  otherwise  than 
so  far  as  it  has  been  a  necessary  consequence  of  the  advice  that 
I  have  given.  The  one  thing  I  am  responsible  for  is  that  advice, 
and  I  stand  here  not  as  the  representative  of  the  Government, 
not  as  an  advocate  of  a  particular  scheme,  but  to  give  you  the 
same  advice,  based  upon  the  same  considerations,  the  result  of 
the  same  reflections.  Although  that  is  a  strange  position  for  a 
man  who  is  speaking  in  public,  it  is  no  strange  position  for  me. 
There  are  the  faces  of  many  here  in  the  audience  who  in  years 
past  have  come  to  me  for  advice  ;  who  have  asked  it  and  taken 
it ;  who  have  shown  by  their  coming  that  they  had  faith  in  my 
judgment.  Well,  I  hope  that  faith  has  not  entirely  passed  away. 

But  in  any  case  I  am  coming  in  the  attitude  of  one  who 
is  giving  advice.  When  I  used  to  see  them  in  my  rooms  at  the 
Temple  I  would  as  soon  have  thought  of  chanting  my  opinion 
as  trying  to  put  it  in  eloquent  words.  It  will  be  the  same  to- 
day. I  shall  put  to  you  in  plain  business  language  the  things 
that  have  haunted  me  for  these  weeks  past  ;  things  that  have 
oppressed  my  thoughts  day  and  night.  In  my  opinion  we  are 
at  a  crisis  of  our  national  life,  and  I  shall  try  to  put  as  plainly 
as  possible,  in  the  simplest  words,  the  facts  which  have  led  me 
to  that  conclusion. 

When  I  began  to  investigate  the  lack  of  dyes  I  found  Eng- 
land consuming  some  two  million  pounds*  worth  of  dyes  per 
annum.  They  were  essential  to  an  industry  of  something  like 
two  hundred  million  pounds  per  annum,  and  on  which  at  least 
a  million  and  a  half  workmen  were  dependent.  And  I  found 
that  of  the  two  million  pounds'  worth  of  dyes  that  was  required 
year  by  year  barely  one-tenth  was  produced  within  our  own 
boundaries.  I  looked  round  for  industries  which  could  at  a 
pinch  supply  the  deficiency.  So  clearly  demarked  from  other 
industries  is  the  great  chemical  industry  of  the  coal-tar  dyes  that 
1  could  find  no  industry  which  could  take  its  place. 

I  found  that  the  stocks  of  dyes,  the  stocks  kept  in  peace 
times — for  no  warning  of  the  intended  war  had  been  vouchsafed 
to  English  customers — I  found  that  those  stocks  were  rapidly 
diminishing,  and  that  practically  there  was  only  one  nation  from 
whom  we  could  expect  help.  I  refer  to  Switzerland,  and  I  knew 
that  in  that  country  pressure  was  being  put  by  Germany  of  the 
most  intense  kind — threatening  to  stop  all  those  supplies  of  their 


MANUFACTURE   OF   DYES   IN   ENGLAND     353 

intermediate  products  on  which  the  Swiss  dyemakers  had  built 
up  their  business,  unless  they  would  promise  that  not  a  pound 
of  their  dye  should,  for  the  whole  period  of  the  war,  come  into 
this  country.  I  found  certainly  some  English  firms  who  were 
manufacturing,  and  manufacturing  successfully,  in  spite  of  the 
competition  of  the  Germans.  But  what  they  could  supply  was 
indeed  inadequate  to  keep  going  the  great  textile  industries 
which  ultimately  depend  to  such  a  large  extent  upon  the  dyeing 
industry. 

That  was  the  serious  immediate  prospect.  But  what  does 
the  future  promise  ?  It  is  that  which  I  have  been  brooding  upon 
ever  since.  Supposing  that  this  war  was  finished.  Supposing 
that  by  the  bravery  of  our  soldiers,  and  by  the  unflinching 
determination  of  our  Government  and  that  of  the  Governments 
of  the  Allies,  we  come  out  of  it  politically  free.  What  position 
do  we  step  into  industrially  ?  We  step  into  the  slavery  of  the 
Germans,  so  far  as  our  textile  and  dyeing  industries  are  concerned, 
as  absolute  as  they  hoped  to  put  us  in  a  political  and  military 
sense. 

What  I  am  saying  is  no  exaggeration.  In  my  perpetual 
converse  with  those  of  you  who  are  practically  interested  in  the 
question  I  have  learned  the  German  methods  of  carrying  on 
business.  I  know  their  way  of  dividing  all  the  nations  up  into 
watertight  compartments,  by  their  system  of  selling  dyes  not  to 
be  exported,  so  that  they  can  put  the  price  up  to  one  nation  and 
down  to  another.  I  know  the  way  in  which  even  the  two  great 
rings,  which  may  be  competitors  one  to  the  other  in  Germany, 
are  united  against  the  foreigner. 

I  say  gravely,  meaning  every  word  that  I  say,  that  if  peace 
were  declared  at  this  moment  you  in  the  English  textile  industry 
would  be  so  much  under  the  domination  of  the  German  dye- 
producing  industry  that  it  could  boycott  you  in  the  way  of  dyes, 
it  could  overcharge  you  for  dyes,  and  it  could  hamper  that 
industry  pending  the  time  when  it  had  the  capital  and  works  to 
challenge  its  very  existence.  And  as  an  Englishman,  that  fills 
me,  I  will  not  say  with  dismay — because  I  have  a  blind  faith  in 
my  countrymen  which  makes  me  believe  that  out  of  the  most 
difficult  position  they  will,  when  they  once  realise  it,  pull  them- 
selves successfully — but  it  made  me  feel  that  it  was  my  business 
to  sound  a  note  of  warning,  and  not  let  people  go  on  thinking 
that  this  trouble  from  shortage  of  dyes  was  one  which  would  be 

23 


354         THE   BRITISH   COAL-TAR   INDUSTRY 

temporary,  lasting  only  during  the  war  time.  No.  It  was  a 
signal  of  danger  which  threatened  us  more  in  peace  than  in  war, 
and  if  we  would  not  listen  to  this  danger  signal  then  our  fate 
was  on  our  own  heads. 

Well,  now,  in  most  things  you  ought  to  consider  how  to  do 
them  before  you  determine  to  do  them.  But  there  are  ex- 
ceptions. This  war  was  an  exception.  I  do  not  think  that 
many  of  us  knew  how  we  were  going  to  struggle  through  this 
war,  but  yet  I  doubt  if  there  is  a  man  in  this  audience  who  did 
not  feel  that  we  must  take  it  up.  I  feel  about  this  industrial 
war  just  the  same.  I  feel  that  the  first  thing  we  have  got  to  do 
is  to  ,say  to  ourselves,  "  That  shall  not  go  on."  And  then  we 
have  to  set  to  work  to  find  out  how  we  can  stop  it. 

But  to  find  out  how  we  can  stop  it  we  must  first  consider 
what  are  the  causes  which  have  led  to  this  strange  position,  that 
a  great  enterprising  industrial  nation — a  nation  which  lives  upon 
export  industries — is  in  the  largest  of  its  export  industries,  which 
I  believe  produces  one-third  of  the  total  exports,  at  the  mercy  of 
the  foreigner.  How  was  it  that  when  the  great  chemical  trade, 
based  on  the  marvellous  way  in  which  coal-tar  products  will 
assume  myriad  forms  and  myriad  different  properties,  when  that 
El  Dorado  was  discovered,  far  more  valuable  than  the  Rand  ever 
will  be,  how  was  it  that  England  did  not  have  its  share  ? 

Was  it  discovered  by  foreigners  ?  It  was  started  by  an 
Englishman.  Was  it  that  foreigners  alone  had  the  natural 
resources  to  carry  it  on  ?  For  years  practically  all  the  raw 
materials  wanted  for  this  industry  were  sent  out  in  an  untreated 
state  from  England.  Then  why  was  it  ? 

Gentlemen,  we  have  got  to  look  the  truth  in  the  face.  It 
was  for  no  other  reason  than  the  English  dislike  of  study.  The 
Englishman  is  excellent  in  making  the  best  of  the  means  at  his 
disposal,  but  he  is  almost  hopeless  in  one  thing.  He  will  not 
prepare  himself  by  intellectual  work  for  the  task  that  he  has  to 
do.  Now  in  the  last  fifty  years  the  knowledge  of  the  world, 
the  additions  to  that  which  we  know,  which  have  been  piled  up 
from  the  work  of  ten  thousand  independent  investigators,  each 
applying  himself  to  one  thing,  have  made  it  so  that  with  regard 
to  each  subject  there  is  a  vast  amount  of  the  "  known."  And  a 
wise  man  who  means  to  deal  with  a  subject  will  master  what  is 
known  before  he  attempts  the  problem  of  what  he  can  do.  That 
is  what  the  Germans,  who  were  rightly  ambitious,  accepted  as 


MANUFACTURE   OF   DYES   IN   ENGLAND    355 

the  condition  of  success  in  industry.  If  you  talk  to  any  German 
who  is  engaged  in  any  industry  you  will  find  that  he  knows 
about  it  all  that  can  be  known. 

I  admit  that  it  does  not  make  him  a  more  pleasant  com- 
panion. Once  I  found  myself  on  the  top  of  one  of  the  Dolomite 
Mountains,  and  the  only  other  person  there  besides  the  guides 
was  a  German.  I  found  out  that  he  was  a  chemist,  and  I  began 
to  talk  upon  a  chemical  subject.  He  told  me  he  was  only  an 
organic  chemist.  He  had  not  exhausted  my  resources,  and  I 
began  to  talk  of  coal  tar  and  pharmaceutical  products.  Then  he 
told  me  that  he  was  a  coal-tar  by-product  chemist.  That  did  not 
beat  me,  because  I  had  just  been  righting  a  case  of  canary  yellow. 
I  thought  I  would  get  some  subject  which  was  common  to  us, 
and  I  slipped  into  the  subject  of  canary  yellow.  Still  the  same 
ominous  silence  for  a  time,  and  then  he  said,  "  I  am  only  a  coal- 
tar  chemist  dealing  with  blues."  But  I  had  not  finished.  With 
an  Englishman's  pertinacity,  not  believing  I  was  beaten,  I  racked 
my  brains  for  a  coal-tar  blue — I  had  had  to  advise  on  some  cases 
— and  I  gradually,  without  a  too  obvious  change  of  subject, 
slipped  into  that.  Then  he  finally  defeated  me,  because  he  said 
in  equally  solemn  tones,  but  equally  proud  of  the  fact,  "  I  only 
deal  with  methyl  blues." 

That  gives  you  an  idea  of  the  way  that  a  German  is  willing 
to  give  up  everything  so  as  to  concentrate  on  the  subject  with 
which  he  has  to  deal.  It  may  limit  his  general  view  of  life.  I 
confess  that  it  is  almost  worse  than  wearing  blinkers.  Goggles 
are  the  only  thing  I  can  think  of  which  at  all  describe  the  mental 
limitations.  But  this  makes  the  Germans  most  formidable  in 
industrial  questions.  It  makes  them  thorough  in  that  which 
they  have  to  do. 

Now,  apart  from  certain  business  methods  which  I  may  have 
to  refer  to  later  on,  I  believe  the  sole  cause  of  England's  falling 
back,  and  Germany's  possession  of  this  great  industry,  is  the 
fact  that  the  Germans  are  perfectly  prepared  to  undertake  the 
intellectual  study  necessary  to  master  the  new  science.  The 
English,  I  believe,  could  do  it  just  as  well,  and  you  will  find  in 
their  great  works  English  chemists  as  highly  respected  as  the 
German,  and  as  efficient.  But  unfortunately  the  holders  of 
capital  in  England  have  had  little  sympathy  with  knowledge  that 
they  did  not  themselves  possess.  As  I  have  been  talking  these 
matters  over  with  people — energetic,  good,  industrial  producers 


356         THE   BRITISH   COAL-TAR   INDUSTRY 

— I  have  always  found  that  when  I  commenced  to  talk  about  the 
intellectual  study  necessary  to  deal  with  chemical  science  there 
has  always  been  that  tone  recalling  the  voice  of  the  sluggard, 
"  You  waked  me  too  soon." 

They  know  the  time  is  coming  when  they  will  have  to  do  it, 
but  they  hope  that  during  their  time  the  traditional  ways  of  their 
fathers  may  be  sufficient,  and  let  the  next  generation  face  the 
intellectual  difficulty  of  study.  The  consequence  has  been  that 
inventions  —  great  inventions — have  fallen  dead  in  England. 
They  have  been  offered  in  Germany  ;  they  have  been  studied  by 
instructed  minds  ;  they  have  been  accepted.  And  the  con- 
sequence has  been  great  industrial  production,  the  fruit  of  which 
all  the  rest  of  the  world  has  received.  But  in  England,  "  Well, 
ah  !  yes.  It  has  not  been  tried.  It  is  difficult/'  It  is  given  to 
somebody  who  has  not  disciplined  himself  like  the  Germans  do, 
and  he  finds  difficulties,  and  then  gradually  the  thing  is  dropped. 
For  you  must  remember  that  because  the  masters,  the  heads,  the 
capitalists,  have  not  got  sympathy  with  this  self-preparation  for 
the  difficult  tasks,  there  is  no  career  for  the  young  men  who  are 
willing  to  study.  What  can  they  do  ?  They  are  paid  salaries 
quite  insufficient  for  the  training  they  have  to  go  through,  and 
for  the  learning  they  have  acquired.  The  consequence  is,  that 
when  I  am  asked  how  it  is  that  we  are  so  poorly  represented  in 
the  industrial  ranks  by  chemists,  I  say,  "  Make  a  career  for  your 
young  chemists,  and  then  you  will  see."  We  have  not  done  so. 

Now  that  is  the  cause,  and,  so  far  as  is  material,  the  sole 
cause,  of  the  German  supremacy.  Remember  that  there  is  not 
one  single  thing  in  which  we  are  at  a  disadvantage  by  natural 
position.  It  is  perfectly  true  that  in  the  Creation,  by  some 
blunder,  the  most  valuable  deposit  of  potash  was  put  in  the 
centre  of  Germany,  but  we  can  get  potash  from  elsewhere  if  we 
want  it.  As  to  coal,  and  the  sources  of  the  coal-tar  industry,  we 
have  them  in  richer  quantity  than  even  Germany  itself.  The 
one  thing  is  the  difference  in  the  human  element,  and  this 
is  not  a  difference  in  intellectual  capacity,  but  in  the  industry  and 
in  the  willingness  to  study  to  the  bottom  the  subject  with  which 
you  have  to  deal. 

Gentlemen,  that  is  my  opinion  of  the  cause  of  England's 
inferiority,  and  I  ask  myself  at  once,  "  Is  that  a  cause  which  must 
permanently  operate  ? "  The  answer  is,  of  course,  *c  No."  But 
it  is  for  us  to  reform  ourselves.  Otherwise  no  relief  can  come. 


MANUFACTURE   OF   DYES   IN    ENGLAND    357 

It  is  impossible  that  we  can  get  a  chemical  industry  like  the 
German's  unless  we  are  willing  to  train  ourselves  for  it,  to  have 
faith  in  it,  to  embark  our  capital  in  it,  and  in  this  way  take  the 
steps  which  lead  to  it.  Consequences  follow  causes  in  this 
world  ;  and  to  hear  people  grumble  at  this  difficulty  about  the 
dyes  when  one  thinks  they  have  neglected  all  the  necessary 
causes  to  produce  the  industry,  would  make  me  feel  almost 
impatient  if  it  did  not  make  me  sorrowful. 

The  question  is,  then,  has  the  condition  of  things  become  so 
permanent  that  it  is  too  late  to  do  anything  ?  Here  I  confess 
that  I  feel  cheerful.  Let  me  deal  for  a  moment  with  the 
difficulties  that  appear  to  one.  The  first  is  that  there  is  a  lack  of 
the  necessary  technical  skill.  I  have  a  great  difficulty  in  returning 
a  polite  answer  to  that.  To  my  mind  it  is  nonsensical.  We 
have  the  command,  and  we  shall  in  peace  still  more  have  the 
command,  of  abundant  technical  skill  to  create  the  industry.  You 
must  remember  this,  that  in  the  long  catalogue  of  dyes  (over 
which  I  have  been  poring  all  these  weeks)  the  vast  number  are 
dyes  the  processes  for  the  manufacture  of  which  are  well  known. 
I  do  not  say  that  the  man  who  is  practised  in  it  will  not  get  a 
better  yield,  or  that  his  handiwork  will  not  be  more  certain.  Of 
course  it  will.  But  there  are  no  people  better  qualified  to  learn 
by  experience  than  the  English  people  themselves,  and  the  whole 
of  these  dyes  can  be  manufactured  with  as  great  certainty  in 
England  if  we  put  up  the  proper  plant  and  choose  the  proper 
men  to  guide  it. 

Now  let  me  go  to  the  more  recent  dyes,  those  that  have 
hardly  made  their  way  into  commerce,  but  the  qualities  of 
which  show  that  they  will  be  very  desirable.  It  is  perfectly 
true  that  if  you  want  to  manufacture  these  on  an  industrial 
scale  you  will  previously  have  to  study  in  the  laboratory,  by 
observation  of  the  reactions,  how  to  get  the  best  results.  But 
you  will  be  astonished  how  few  the  processes  are  in  this  great 
industry,  and  the  extent  to  which  they  are  simply  the  repetition 
of  the  same  processes  with  different  substances  and  under 
different  conditions.  The  sole  difficulty  which  separates  brilliant 
success  from  comparative  failure  is  that  study  has  shown  how 
to  regulate  the  conditions  so  as  to  make  the  results  most 
favourable. 

There  is  no  mystery  to  the  chemist.  There  is  that  which 
requires  study  before  he  can  arrive  at  it  ;  but  if  you  are  going 


358         THE   BRITISH   COAL-TAR   INDUSTRY 

to  be  daunted  by  that,  then  the  rest  of  my  speech  will  not 
interest  you.  So  that  the  objection  of  not  having  abundant 
technical  skill  to  carry  out  any  industry  that  we  form  is  in  my 
opinion  absolutely  baseless. 

Well,  then  I  am  told,  "  It  is  impossible  to  compete. 
There  are  works  with  a  capital  of  a  hundred  millions  in  Germany. 
Your  foes  are  willing  to  crush  you  by  every  means  they  know, 
and  those  means,  I  can  assure  you,  are  various  and  effective." 

Well,  that  is  a  very  great  fact,  but  if  you  tell  me  that  it  is 
impossible  for  manufacture  to  go  on  in  spite  of  this  competition 
1  will  ask  you  to  turn  your  eyes  not  only  to  this  country,  but 
even  to  Germany,  where  you  find  firms  outside  these  great 
combinations,  who  in  their  own  particular  line  have  a  successful 
business,  and  even  an  export  business,  in  which  they  contrive  to 
flourish — not  to  make  the  gigantic  profits  of  the  rings,  but  still 
to  make  fair  industrial  profits.  In  your  own  country  you  have 
them.  You  have  firms  that  in  spite  of  the  pressure  of  the 
Germans  manufacture  at  a  profit.  And  side  by  side — if  you 
look  back — with  these  firms  there  were  many  other  firms  whom 
the  Germans  feared  sufficiently  either  to  buy  out  or  to  crush 
out.  When  they  realised  that  they  were  capable  of  producing 
in  competition  with  them  they  felt  that  at  great  cost  they  must 
get  rid  of  them.  That,  surely,  is  proof  that  competition  in  pro- 
duction is  not  impossible. 

Remember  this,  that  success  in  production  depends  no 
doubt  on  cheapness,  but  if  you  produce  on  what  I  may  call  an 
economical  unit,  that  is  on  a  scale  which  is  adequately  great, 
the  advantages  from  doing  it  on  an  enormous  scale  are  very 
small  in  comparison.  And  certainly  England,  with  its  rich 
market,  its  demand  for  dyes — and  many  of  these  demands 
capable  of  being  satisfied  with  comparatively  few  dyes, — England 
can  certainly  start  an  industry  in  which  the  manufacture  is  on 
such  a  large  scale  that  it  can  challenge  if  not  equal  the  economies 
of  the  biggest  works. 

Let  me  now  go  to  the  third  objection  which  is  raised  to  the 
possibility  of  our  competing,  and  it  is  raised  in  connection  with 
the  suggestion  that  I  am  defending  here — the  consequence  of 
my  conclusion  that  a  great  national  effort  should  be  made,  and 
a  large  company  formed  capable  of  producing  dyes  on  a  scale 
sufficient  to  satisfy  the  English  demand.  It  is  a  very  curious 
one,  and  yet  you  have  all  heard  it.  I  remember  saying  to  one 


MANUFACTURE   OF   DYES   IN   ENGLAND     359 

with  whom  I  was  discussing  the  matter,  and  who  knew  well 
the  trades  of  Lancashire  and  Yorkshire — "Don't  you  think 
it  would  be  of  infinite  value  to  England  to  have  a  company 
which  would  for  ever  secure  its  dyeing  and  textile  .industries, 
aye,  and  the  great  pigment  industries,  which  must  not  be  for- 
gotten, from  being  overcharged  for  their  dyes  ? "  The  man 
said,  "  But  that  is  not  what  I  am  thinking  about.  I  am  not 
thinking  about  being  overcharged.  My  fear  is  we  shall  be 
undercharged  ! " 

Here  I  was  trying  to  protect  an  English  industry.  I  was 
talking  to  a  man  vitally  interested  in  it,  and  what  was  his  fear  ? 
His  fear  was  that  the  consequence  of  our  doing  it  would  be  that 
you  would  get  dyes  cheaper  than  they  could  be  made,  and  that 
was  what  was  frightening  him.  I  will  tell  you  what  it  reminded 
me  of.  Supposing  there  was  a  question  of  building  a  defensive 
fort  to  protect  the  vital  part  of  a  country,  to  protect,  we  will 
say,  London,  and  the  objection  was  raised,  "  Oh,  but  if  you 
build  it  as  strong  as  that  nobody  will  attack  it,  and  then  how 
will  you  defend  the  spending  of  your  money  ?  " 

I  ask  you  to  think  of  this  objection  seriously,  and  in  the 
light  in  which  I  am  putting  it  to  you.  To  my  mind  it  is  the 
most  universal  and  the  meanest  of  all  the  things  which  influence 
men's  minds  on  this  subject.  They  are  afraid  it  will  be  too 
successful.  They  know  that  if  they  do  not  make  such  a 
company  they  will  be  ruthlessly  overcharged  by  the  Germans. 
Of  that  there  is  not  a  fraction  of  doubt.  They  know  that  if 
they  do  form  this  company  that  cannot  be  so,  and  the  probability, 
they  think,  is  that  your  great  industries  will  have  their  dyes 
cheaper  even  than  they  can  be  made.  They  must  realise  that 
that,  to  a  nation  which  has  a  world-wide  commerce,  is  a  boon 
beyond  estimation,  and  yet  they  are  afraid,  if  they  put  their 
money  in,  that  they  will  win  this  boon  for  their  fellow- 
countrymen. 

What  does  it  mean  ?  It  is  that  ineradicable  defect  of  the 
English  mind,  if  it  has  not  by  travel  or  study  or  reading  got 
rid  of  its  insularity.  I  used  to  sit  for  a  constituency,  an 
agricultural  one  in  the  South,  and  I  never  could  get  out  of  the 
head  of  any  one  farmer  that  his  real  competitor  was  the  man 
living  next  door  to  him.  He  did  not  realise  that  this  insular 
idea  of  being  afraid  that  the  man  next  door  will  get  the  better 
of  you  for  a  penny,  or  that  his  goods,  which  are  not  quite  as 


360         THE   BRITISH   COAL-TAR   INDUSTRY 

good  as  yours,  will  still  be  treated  alike  with  yours,  is  the  thing 
which  has  prevented  all  co-operation  among  them  in  the  south. 
While  Denmark,  a  poor  country,  has  been  rolling  up  its  wealth 
by  combined  action,  our  English  people  stand  apart,  and  are  still 
as  unfitted  for  helping  the  wholesale  trade  of  the  world  as  if  it 
were  almost  fifty  years  ago. 

What  this  objection  means  is,  you  are  afraid  that  Mr  So- 
and-So,  who  has  not  subscribed,  will  get  all  the  benefit  you  have 
won  by  your  subscription.  You  do  not  doubt  that  you  will  win 
it  for  your  country.  You  do  not  doubt  that  you  will  win  it 
for  yourselves.  You  do  not  doubt  that  in  this  way,  so  far  from 
industries  being  harried,  they  will  be  put  in  an  undeservedly 
fortunate  position.  And  yet  you  do  not  want  to  do  it  because 
the  gain  will  come  to  your  trousers  pocket  instead  of  to  your 
waistcoat  pocket.  Instead  of  coming  in  dividend  it  will  come 
in  the  lower  price  of  dyes. 

So,  if  I  could  believe  that  the  formation  of  this  company 
would  force  the  Germans  for  one  year  or  two  years  or  twenty 
years  to  sell  their  dyes  at  less  than  cost  price,  I  should  come  to 
you  and  say,  "  You  have  got  a  chance  now  to  save  yourselves 
and  England,  and  to  put  yourselves  and  England  in  a  position 
of  vantage  in  competition  in  foreign  lands  that  you  have  not 
deserved  but  that  you  are  going  to  get." 

But,  gentlemen,  I  frankly  tell  you  that  I  do  not  think  you 
are  going  to  have  such  a  good  time  as  that.  1  will  tell  you  why. 
If  a  great  company  is  formed  that  is  efficient  and  that  produces, 
as  an  efficient  English  company  will  produce,  at  fair  prices,  it 
will  cost  the  Germans  too  much  to  sell  below  cost  price  here. 
For  this  reason  :  once  satisfy  the  English  market  with  these  low- 
priced  dyes,  and  you  free  the  output  of  this  company  to  go  to 
those  Eastern  markets,  out  of  which  the  Germans  derive  the 
profits  which  enable  them  to  fight  you,  and  you  can  sell  there 
at  fair  prices,  and  the  Germans  will  either  lose  the  market  or 
there,  too,  they  must  drop  their  prices. 

I  think  you  will  find  that  dropping  prices  all  round  is  not  a 
good  way  of  increasing  your  profits.  You  are  business  men.  I 
am  not  a  business  man,  but  my  opinion  is  that  they  will  find 
that  it  is  better  to  leave  you  alone,  better  to  leave  you  to  supply 
yourselves  than  to  set  free  such  a  formidable  output  as  a  great 
company  would  make  to  compete  with  them  in  the  other  markets 
of  the  world. 


MANUFACTURE   OF   DYES   IN   ENGLAND    361 

What  does  all  this  lead  to  ?  It  leads  to  this.  In  my  opinion 
there  must  be,  in  order  to  give  England  industrial  freedom  in 
this  group,  which  is  almost,  I  should  think,  or  quite,  the 
greatest  group  of  its  industries — there  must  be  a  great  national 
effort  to  create  a  company,  a  company  working  under  the  con- 
ditions of  other  companies,  suffering  from  its  blunders  and 
profiting  by  its  wisdom. 

But  there  are  three  conditions,  and  unless  those  three  con- 
ditions are  all  satisfied  it  will  be  a  failure. 

The  first  condition  I  lay  down  is  that  it  must  be  large. 
Politically,  the  Germans  are  frankly  the  foes  of  small  nations. 
They  consider  that  small  nations  are  to  be  eaten  up.  Industrially, 
this  great  embodiment  of  the  German  idea,  the  combination  of 
the  dye  manufacturers,  behaves  to  small  manufacturers  exactly 
as  Germany  seeks  to  behave  to  small  nations.  It  is  hopeless  to 
suppose  that  if  there  are  sporadic  attempts,  all  small,  they  will 
not  be  either  dragged  into  a  combine,  or  crushed  by  a  combine, 
or  in  one  of  the  many  other  ways,  which  you  all  know,  put  out 
of  existence.  It  must  be  large,  and  therefore  independent,  and 
therefore  beyond  attack. 

There  is  another  thing.  It  must  be  national  in  this  sense  : 
it  must  be  removed  for  ever  from  the  temptation  of  listening 
itself  to  the  voice  of  the  charmer  and  entering  into  a  combine. 

We  must  have  a  company  that  is  not  only  powerful,  but  one 
the  loyalty  of  which  is  necessarily  beyond  all  doubt,  and  that  we 
can  only  get  if  it  is  assisted  by  the  Government,  on  the  terms 
that  the  Government  can  stop  it  from  ever  entering  into  the 
backward  path  which  would  ruin  its  national  utility.  Most  of 
you  like  the  idea,  I  can  see,  of  its  being  large,  and  of  its  being 
kept  always  true  and  faithful  to  its  national  aim. 

Now  I  am  going  to  tell  you  the  third  condition,  which 
concerns  you.  It  must  be  co-operative.  The  producer  must 
be  the  consumer.  You  will  never  link  up  all  these  industries 
unless  those  who  use  the  dyes  are  included,  the  textile  people 
as  well  as  the  dyeing  people,  and  those  who  are  in  the  great 
pigment  trade.  Unless  all  those  who  are  about  to  consume 
have  an  interest  in  the  production,  and  therefore  supply  a  pre- 
ferential market,  you  will  never  succeed  in  making  the  com- 
pany relieve  the  national  need.  If  1  had  had  the  millions  I 
wanted  offered  me  on  the  Stock  Exchange  for  a  company  which 
would  be  free  from  all  trammels,  which  would  have  no  connection 


362         THE   BRITISH   COAL-TAR   INDUSTRY 

with  the  trade,  the  shares  of  which  would  be  bought  as  the  others 
that  are  called  industrials  on  the  Stock  Exchange,  where  every 
penny  of  profit  it  made  would  be  squeezed  out  of  it  for  the 
benefit  of  the  then  holders  of  the  shares,  who  would  care  nothing 
for  the  holders  of  the  next  year  or  for  the  future  of  the  company, 
I  would  have  said  at  once,  "  It  is  doomed  to  failure,"  and  its 
failure  would  be  only  the  more  marked  because  it  was  gigantic. 

You  must  realise  that  you,  the  consumers,  should  loyally  all 
combine  with  the  producing  company,  and  then  I  will  defy  the 
German  or  any  other  competition  to  break  down  that  bond  of 
union.  Remember  this.  The  only  thing  which  will  ensure  a 
combine  or  a  ring  against  failure  is  co-operation  between  the 
producer  and  the  consumer.  I  remember  one  of  the  earliest 
cases  that  came  before  me.  It  was  a  case  of  a  very  great  in- 
dustry, and  we  were  told  that  it  was  entirely  in  the  hands  of 
such  a  ring  formed  in  such  a  city  in  Germany.  Well,  what 
happened  ?  We  got  the  producers  and  the  consumers  together 
and  said,  "  If  you  will  produce  the  article  yourselves  you  can 
defy  rings.  How  can  they  touch  you  ?  (It  happened  to  be  a 
question  of  a  metal.)  You  can  buy  in  the  markets  of  the  world. 
It  is  produced  everywhere.  No  one  can  run  up  the  price  against 
you,  and  therefore  the  worst  that  can  happen  is  that  you  are  on 
equal  terms  with  them." 

Now  some  of  you  will  say,  "  Oh,  yes,  but  is  not  this  a  viola- 
tion of  the  chief  commandment,  c  You  shall  buy  in  the  cheapest 
market  *  ? "  Is  it  ?  Remember  this,  that  in  considering  what 
is  cheap  you  must  not  look  at  the  money  that  passes,  but  at  the 
consequences  of  the  purchase  too.  The  man  who  says,  "  I  will 
buy  for  five  years  at  a  discount  of  five  per  cent.,  with  the  certainty 
that  I  shall  have  to  pay  fifteen  per  cent,  more  for  the  next  ten 
years,"  and  thinks  he  is  buying  in  the  cheapest  market,  is,  I 
suggest,  a  bad  student  of  economics.  It  is  not  buying  in  the 
cheapest  market  if  you  buy  something  which  destroys  your  real 
security  for  cheapness,  which  prevents  you  from  being  over- 
charged. And  I  am  perfectly  certain  that  when  the  idea  of  loyal 
co-operation  gets  hold  of  Lancashire  and  Yorkshire  the  foes  of 
England  in  the  industrial  world  will  begin  to  tremble.  We 
have  had  a  time  of  peace  in  England,  and  we  have  never  thought 
of  dangers  industrial  or  national.  But  there  are  these  dangers, 
and  even  though  there  may  not  be  another  war,  as  we  trust  there 
will  not  be,  there  is  perpetual  war  going  on  industrially,  and  it 


MANUFACTURE   OF   DYES   IN   ENGLAND     363 

is  not  based  on  the  ideas  of  each  man  doing  his  best  and  of  fair 
sale  and  fair  purchase.  It  is  based  on  what  in  the  industrial 
world  corresponds  to  war  in  the  political  world,  and  if  you  do 
not  realise  that,  if  you  will  not  stand  by  one  another  as  producer 
and  consumer,  and  you  let  the  producer  go  down  under  his 
enemies,  so  that  in  turn  they  have  the  mastery  of  you,  then  all 
I  can  say  is  that  as  consumers  you  have  been  buying  in  the 
dearest  market,  and  you  will  deserve  the  consequences  that 
you  get. 

Now,  gentlemen,  I  have  come  to  the  conclusion  of  which 
I  told  the  Government.  I  have  nothing  to  do  with  the  particular 
form  in  which  the  Government  have  followed  out  that  for 
which  I  am  responsible  as  an  adviser.  You  must  have  a  large 
company — a  company  with  national  control  so  far  as  to  keep 
it  in  the  right  path  ;  and  you  must  have  a  company  which  is 
co-operative  between  the  producer  and  the  consumer.  If  you 
do  that,  I  can  warrant  it  a  long  and  successful  life  ;  but  if  you 
attempt  to  leave  out  any  one  of  these  three  essentials,  it  is  pre- 
doomed  to  failure. 

Just  let  me  say  one  or  two  words  in  conclusion.  Supposing 
our  War  Minister  had  been  in  the  last  few  years  buying  in  the 
cheapest  market  for  the  sake  of  cheapness,  and  that  he  had 
had  the  munitions  of  war  manufactured  by  Krupps,  of  Essen. 
Gentlemen,  I  think  he  would  have  been  lynched  about  three 
months  ago.  You  would  have  realised  when  the  moment  of 
need  came  that  your  sources  of  supply  were  cut  off.  Now, 
gentlemen,  there  are  munitions  of  peace  which  are  essential  for 
the  defence  of  the  great  industries  of  the  country,  which  are 
vital.  There  are  munitions  of  peace  as  to  which  you  have  to 
take  the  same  precautions  as  in  regard  to  munitions  of  war. 

You  have  to  realise  that,  so  far  as  it  is  possible,  a  country 
should  be  in  such  a  position  that  if  its  supplies  are  cut  off,  for 
any  reason  whatever,  from  outside,  it  should  be  able  to  supply 
itself.  Of  course,  we  realise  that  in  raw  materials  and  in  many 
other  things  we  must  depend  on  supplies  from  outside,  and  that 
is  the  reason  why  we  are  a  nation  that  spends  so  unstintingly 
on  its  fleet.  But  this  is  no  question  of  getting  raw  materials 
from  a  foreign  country.  It  is  a  question  of  being  at  the  mercy 
of  a  country,  not  friendly  disposed,  in  a  matter  where  we  could 
make  ourselves  independent ;  and  it  is  a  case  in  which  we  know 
perfectly  well  what  are  the  morals  of  that  country  in  regard  to 


364         THE   BRITISH   COAL-TAR   INDUSTRY 

its  behaviour  to  other  nations.  Therefore  I  say  you  must  look 
upon  it  as  if  it  were  one  of  those  necessary  munitions  of  peace 
which  you  must  see  adequately  manufactured  among  yourselves. 

Some  will  say — there  is  none  here,  I  trust — what  I  heard 
of  a  great  dealer  saying,  "  Oh,  but  I  am  a  business  man.  I  only 
look  at  things  as  business  propositions,  and  a  tenth  of  a  penny 
would  make  me  buy  everything  from  Germany  rather  than  from 
England."  At  that  very  moment  tens  of  thousands  of  men 
were  exposing  their  lives  in  the  trenches  to  protect  that  man 
and  his  money.  I  wonder  how  many  would  have  been  there  if 
it  was  always  thought  a  brilliant  thing  for  a  man  to  look  on  every- 
thing from  the  point  of  view  of  a  business  proposition  ? 

If  that  is  being  done  by  the  recruits,  what  are  you  and  I  going 
to  do  for  our  country  ?  You  cannot  go  to  the  trenches,  and  yet 
I  believe  you  are  all  willing  and  burning  to  do  what  you  can 
for  your  country.  Well,  this  is  your  part.  You  can  protect 
your  country  by  taking  care  that  when  peace  comes  it  shall  be 
under  no  subordination.  That  is  what  I  ask  you  to  do.  A 
great  writer  has  said,  "  There  is  nothing  more  desirable  in  life 
than  to  be  wise  at  a  great  moment."  This  is  a  great  moment. 
Be  wise. 


XXVII.:    1915 

GERMAN    CHEMICAL    INDUSTRY   THIRTY 
YEARS  AGO 

BY  THE  RIGHT  HON.  SIR  HENRY  ROSCOE,  F.R.S. 

(Journal  of  the  Society  of  Chemical  Industry^  3Oth  January  1915,  p.  65) 

THE  following  short  report,  written  by  myself  for  the  Royal 
Commission  on  Technical  Instruction,  of  which  I  was  a  member, 
was  printed  in  1882.  This  shows  that  even  in  those  early  years 
the  Germans  had  seized  upon  the  methods  which  have  made 
their  chemical  industries  so  successful,  and  that  money  cannot 
secure  success  unless  it  is  accompanied  by  perfect  scientific 
method,  and  above  all  by  the  recognition  of  the  importance  of 
original  investigation  : — 

ON  THE  INFLUENCE  OF  TECHNICAL  EDUCATION  ON  CERTAIN 
BRANCHES  OF  CHEMICAL  INDUSTRY 

We  have  here  collected  our  notes  on  certain  special  industries, 
viz.  (i)  chemical  colours,  (2)  beet-sugar,  and  (3)  the  alkali  trade, 
upon  which  the  influence  of  technical  education  is  plainly 
observable. 

Influence  of  Technical  Training  on  the  Chemical  Colour  Industry 
of  Germany  and  Switzerland 

Among  the  coal-tar  colour  works  visited  by  the  Commissioners 
were  those  erected  on  the  banks  of  the  Rhine  at  Basle  by  Messrs 
Bindschedler  &  Busch.  These  works,  though  far  less  extensive 
than  those  of  Messrs  Meister,  Lucius  &  Brttning,  at  Hdchst, 
or  of  the  Baden  Aniline  and  Soda  Works  at  Ludwigshafen,  are 

365 


366         THE   BRITISH   COAL-TAR   INDUSTRY 

carried  on  in  a  no  less  scientific  spirit,  and  the  general  method  of 
working  adopted  in  all  these  establishments  is  identical. 

The  first  principle  which  guides  the  commercial  heads  of  all 
the  Continental  colour  works  is  the  absolute  necessity  of 
having  highly  trained  scientific  chemists  not  only  at  the  head  of 
the  works,  but  at  the  head  of  every  department  of  the  works 
where  a  special  manufacture  is  being  carried  on.  In  this  respect 
this  method  of  working  stands  in  absolute  contrast  to  that  too 
often  adopted  in  chemical  works  in  this  country,  where  the  con- 
trol of  the  processes  is  left  in  the  hands  of  men  whose  only  rule 
is  that  of  the  thumb,  and  whose  only  knowledge  is  that  bequeathed 
to  them  by  their  fathers. 

On  entering  the  works  of  Messrs  Bindschedler  &  Busch  one 
is  struck,  in  the  first  place,  with  the  adaptation  of  means  to  ends, 
with  the  substantially  built,  well-lighted,  well-ventilated  work- 
shops, and,  above  all,  with  the  all-pervading  cleanliness  and 
neatness.  But  it  is  not  of  these  things  that  we  now  desire  to 
speak,  but  rather  of  the  method  by  which  their  business  is 
conducted.  In  the  first  place,  then,  the  scientific  director 
(Dr  Bindschedler)  is  a  thoroughly  educated  chemist,  cognisant 
of  and  able  to  make  use  of  the  discoveries  emanating  from  the 
various  scientific  laboratories  of  the  world.  Under  him  are 
three  scientific  chemists,  to  each  of  whom  is  entrusted  one  of  the 
three  main  departments,  into  which  the  works  are  divided.  Each 
of  these  head  chemists,  who  have  in  this  instance  enjoyed  a 
thorough  training  in  the  Zurich  Polytechnic,  has  several  assistant 
chemists  placed  under  him,  and  all  these  are  gentlemen  who 
have  had  a  theoretical  education  in  either  a  German  university 
or  in  a  Polytechnic  school.  An  important  part  of  the  system 
has  now  to  be  noticed,  viz.,  that  directly  under  these  scientific 
assistants  come  the  common  workmen,  who  have,  of  course,  no 
knowledge  whatever  of  scientific  principles,  and  who  are,  in  fact, 
simple  machines,  acting  under  the  will  of  a  superior  intelligence. 
The  many  and  great  advantages  of  this  arrangement  are  patent 
to  all ;  and  the  fact  of  having  men  of  education  and  refinement 
in  positions  of  this  kind  renders  the  foreign  manufacturer  who 
adopts  this  system  less  liable  to  annoyance  and  loss  (from 
sources  which  we  need  not  more  nearly  specify)  than  his  English 
competitor,  who  works  on  a  different  plan. 

So  much  for  the  personnel  of  the  works.  Now  for  the  mode 
in  which  they  carry  on  their  work.  To  begin  at  the  beginning, 


GERMAN  CHEMICAL  INDUSTRY  30  YEARS  AGO    367 

we  find  no  less  than  ten  well-equipped,  airy,  experimental 
laboratories  in  these  works,  perfectly  distinct  from  the  workshops 
where  the  manufacturing  processes  are  carried  on.  In  these  ten 
laboratories,  the  chief  departmental  chemists  and  their  assistants 
work  out  their  investigations  respecting  the  production  of  new 
colouring  matters,  or  the  more  economic  manufacture  of  old 
ones.  To  assist  them  in  their  work,  a  complete  scientific  library 
is  at  hand  containing  all  the  newest  researches,  for  these,  as  we 
have  said,  form  the  material  out  of  which  the  colour-chemist 
builds  up  his  manufacture,  and  no  sooner  do  the  results  appear 
of  a  perhaps  purely  scientific  research  which  may  possibly  yield 
practical  issues,  than  the  works-chemist  seizes  on  them  and 
repeats  these  experiments,  modifying  and  altering  them  so  as  at 
last  to  bring  them  within  the  charmed  circle  of  financial  success. 

Thanks  to  Dr  Bindschedler,  we  are  able  to  quote  a  specially 
representative  case,  and  a  clear  description  of  one  such  case  is 
worth  a  host  of  generalities.  Through  the  original  investigations 
of  Messrs  Emil  and  Otto  Fischer,  the  attention  of  the  manufacturer 
was  drawn  to  the  leuco  or  colourless  base  obtained  by  the  action 
of  benzaldehyde  on  dimethylaniline,  inasmuch  as  they  stated 
that  the  salts  of  these  colourless  bases  become  green  on  exposure 
to  air.  Founded  on  these  observations,  an  endeavour  was  made 
to  effect  the  practical  manufacture  of  a  green  colouring  matter 
by  oxidation  of  these  colourless  bodies.  In  order  to  attain  the 
desired  end,  the  following  investigations  had  to  be  made  by  the 
chemist  and  his  assistants  who  were  to  conduct  the  operations  : — 

(1)  A  cheap  method  had  to   be   found   for   manufacturing 
benzaldehyde. 

(2)  A  profitable  mode  of  making  the  leuco  base  had  to  be 
worked  out. 

(3)  The    proper  oxidising  agents  and  their  best  method  of 
application  had  to  be  determined. 

(4)  The   best  method  of  purifying  and  of   crystallising  the 
green  colouring  matter  had  to  be  discovered. 

The  laboratory  experiments  on  the  above  points  having 
proved  so  far  successful  as  to  give  prospects  of  good  results, 
operations  on  a  somewhat  larger  scale  were  started,  and  these 
yielding  a  satisfactory  issue,  the  manufacture  proper  of  the 
colouring  matter,  now  well  known  as  malachite  green,  on  the 
technical  scale  was  commenced,  all  the  operations  being  watched 
by  and  constantly  being  under  the  control  of  the  chemists.  But 


368         THE   BRITISH   COAL-TAR   INDUSTRY 

even  now  their  scientific  work  is  by  no  means  ended.  Continuous 
laboratory  experiments  go  on  for  the  purpose  of  rinding  improve- 
ments in  the  mode  of  manufacture.  Thus,  for  example,  the 
improved  yield,  both  as  to  quality  and  quantity,  of  the  benzal- 
dehyde  is  a  matter  of  investigation.  Again,  the  synthetic  pro- 
duction of  the  pure  leuco  base  by  a  more  direct  process  is  sought 
for,  so  as  to  get  rid  of  loss  in  working,  and  to  obtain  a  yield  as 
close  as  possible  to  that  pointed  out  by  theory.  In  the  same 
way  improvements  in  the  materials  used  for  oxidation,  and  in 
their  application,  are  made,  so  as  to  effect  the  oxidation  quanti- 
tatively, without  the  formation  of  by-products.  Lastly,  the 
action  of  various  solvents  is  examined,  so  as  to  obtain  the  best 
form  of  the  crystallised  colouring  matter.  As  indicating  the 
value  of  these  improvements  made  after  the  colour  became  a 
marketable  article,  it  is  only  necessary  to  state  that  the  price 
of  the  crystallised  oxalate  has  been  reduced  from  £2  to  £1,  43. 
per  kilo. 

The  foregoing  may  serve  to  give  a  picture  of  a  really 
scientifically  conducted  works,  where  each  step  in  advance  is 
made  systematically,  as  the  result  of  a  well-devised  plan  of 
operations.  This  is,  indeed,  the  only  means  of  progress,  and 
this  fact  is  so  well  recognised  in  Germany  that  each  of  the  much 
larger  colour  works  at  Hochst  and  Ludwigshafen  possesses  a 
staff  of  from  thirty  to  forty  well-paid  and  thoroughly  trained 
chemists  to  conduct  their  operations. 

But  we  are,  of  course,  far  from  believing  that  because  the 
methods  adopted  in  these  foreign  colour  works  are  scientific  and 
productive  of  good,  those  made  use  of  in  all  English  works  must 
therefore  be  unscientific  and  bad.  Taking  the  whole  applications 
of  chemical  science  we  may,  no  doubt,  with  truth  say  that  the 
English  industrial  chemists  have  been  at  least  as  successful 
commercially  and  certainly  as  productive  in  new  and  important 
discoveries  as  their  Continental  rivals.  The  Germans  and 
Swiss,  however,  have  been  and  still  are  distinctly  before  us,  not 
only  in  the  facilities  which  they  possess  of  obtaining  the  highest 
technical  training  in  their  numerous  universities  and  polytechnic 
schools,  but  what  is  even  more  to  the  point  before  us,  is  the 
general  recognition  of  the  value  and  importance  of  such  training 
for  the  successful  prosecution  of  any  branch  of  applied  science. 

The  following  statistics  give  some  idea  of  the  magnitude 
of  the  colour  works  of  Messrs  Meister,  Lucius  &  Brtlning, 


GERMAN  CHEMICAL  INDUSTRY  30  YEARS  AGO    369 

at  Hflchst,  near  Frankfort,  referred  to  above,  and  founded 
in  1862. 

The  establishments  occupy  an  area  of  1 50  acres,  of  which  20 
are  covered  with  buildings.  The  staff  includes  51  scientific 
chemists,  50  foremen,  15  managers  and  engineers,  and  77  clerks 
and  commercial  men,  with  1400  workpeople.  The  works  possesses 
its  own  railways,  41  boilers,  with  a  heating  surface  of  4000  square 
yards,  and  71  motors,  either  steam,  water,  or  gas  engines.  The 
workmen  and  officials  are  domiciled  in  houses  belonging  to  the 
company,  and  restaurants,  baths,  sick  clubs  and  pension  funds 
have  been  established  for  the  good  of  the  employes.  There  is 
also  a  fire-brigade  with  5  hand  engines  and  i  steam  fire-engine. 
The  total  supply  of  water,  from  145  fire-cocks,  amounts  to  30,000 
cubic  feet  per  hour. 

In  1882  the  products  of  these  works  amounted  to  : — 

(1)  6,600,000  Ib.  weight  of  alizarin. 

(2)  2,200,000  Ib.  weight  of  aniline  oil. 

(3)  1,540,000  Ib.  weight  of  aniline,  resorcin,  and  naphthol. 

Colours 

The  following  are  the  separate  products  classed  together 
under  the  last  head  : — 

Aniline  and  aniline  salts. 

Fuchsine  (no  arsenic  used  in  its  preparation). 

Methyl  violet. 

Green  and  blue  colours. 

Eosin  colours. 

Naphthol  colours. 

Alizarin  and  artificial  indigo. 

Quinolin  derivative  (kairin,  a  new  substitute  for  quinine). 

Acids. 

The  most  important  raw  materials  employed  in  manufacturing 
the  foregoing  products  are  as  follows  : — 

40,000  tons  coal. 
3,000    „     tar  products. 
2,400    „     caustic  soda. 
400    „     potash  salts. 
2,900    „     carbonate  of  soda. 
17,400    „     sulphuric  acid. 

24 


370         THE   BRITISH   COAL-TAR   INDUSTRY 

10,100  tons  various  other  acids. 
1,500    „     iron  borings  and  filings. 

250    „     wood  spirit  and  spirits  of  wine. 
1,000    „     various  chemicals. 
6,800    „     common  salt. 
2,050    „     carbonate  of  lime. 

The  whole  of  the  sulphuric,  hydrochloric,  and  nitric  acids 
used  is  made  on  the  works. 

From  about  70  to  80  per  cent,  of  all  the  aniline  colours  manu- 
factured are  exported,  the  remainder  being  used  in  Germany. 

About  90  per  cent,  of  the  total  make  of  alizarin  is  exported 
chiefly  to  England,  but  considerable  quantities  find  their  way  to 
America,  Russia,  France,  Holland,  Spain,  and  Italy. 

One  of  the  most  recent  and  most  interesting  additions  to  the 
above  list  of  products  is  a  derivative  of  quinolin,  termed  kairin, 
lately  discovered  by  Emil  Fischer.  This  substance,  which  is 
now  being  made  at  Hochst  at  the  rate  of  about  22  Ib.  daily,  has 
been  shown  to  possess  important  febrifuge  properties,  even 
exceeding  quinine  in  activity,  and  it  is  not  impossible  that  this 
artificial  product  obtained  from  coal  tar  may  be  the  means  of 
supplanting  altogether  the  natural  alkaloid.  The  importance  of 
this  discovery,  should  it  serve  the  above  purpose,  can  of  course 
hardly  be  overrated,  and  it  will  then  add  another  and  most 
striking  example  to  the  numerous  ones  which  already  exist  of  the 
immense  importance  to  the  human  race  of  researches  in  purely 
scientific  organic  chemistry,  which  at  one  time  appeared  to  have 
no  practical  value  or  possible  application.  It  may,  therefore, 
serve  again  to  point  the  moral,  which  cannot  be  too  strongly 
insisted  upon,  that  it  is  only  by  the  highest  and  most  elaborate 
achievements  of  pure  scientific  investigation  that  the  greatest 
practical  advantages  to  mankind  can  be  secured. 


XXVIII. :    1915 

THE    MANUFACTURE    OF    DYESTUFFS 
IN    BRITAIN 

BY  PROFESSOR  W.  M.  GARDNER,  M.Sc.,  F.I.C. 

I 

A  SUMMARY  AND  AN  APPEAL 
(Nature^  2ist  January  1915,  p.  555) 

THE  speech  of  Lord  Moulton  in  Manchester  on  8th  December 
1914  was  a  notable  event,  even  in  these  days  of  strenuousness 
and  surprise.  For  although  he  was  careful  to  disclaim  any  official 
sanction  of  the  views  he  expressed,  it  was  common  knowledge 
that  the  Government  had  requisitioned  his  services  in  investigat- 
ing the  question  of  the  shortage  of  dyestuffs,  and  had  based  its 
policy  largely  on  the  advice  he  gave  as  the  outcome  of  his 
investigation. 

The  general  outline  of  the  crucial  position  in  which  the 
British  textile  trades  are  placed  at  the  present  time  is  well 
known.  At  least  1,500,000  operatives  are  engaged  in  the 
various  branches  of  the  trade,  which  has  an  annual  value  of 
£200,000,000.  Nearly  the  whole  of  this  vast  industry  depends 
for  its  commercial  success  upon  the  use  of  dyestuffs,  which  cost 
about  £2,000,000  per  annum,  and  only  about  10  per  cent,  of  the 
necessary  quantity  of  dyestuff  is  made  in  this  country.  Before 
the  war,  between  80  to  90  per  cent,  of  our  dyewares  was 
imported  from  Germany,  and  this  supply  is  now  entirely  cut  off. 
Unless,  therefore,  immediate  steps  are  taken  greatly  to  increase 
our  national  output  and  the  supply  from  neutral  countries  (chiefly 
Switzerland),  a  catastrophe  will  very  quickly  overtake  the  great 
textile  and  associated  industries. 


372         THE   BRITISH    COAL-TAR   INDUSTRY 

The  magnitude,  gravity,  and  imminence  of  the  crisis  clearly 
pointed  to  the  necessity  for  Government  action,  and  a  "  Chemical 
Supplies  Committee  "  was  appointed  to  confer  with  the  Board  of 
Trade  on  the  position.  This  committee  included  a  number  of 
well-known  chemists,  and  manufacturers  and  users  of  chemicals 
and  dyestuffs.  The  investigations  of  Lord  Moulton  and  of  this 
committee  are  understood  to  have  formed  the  basis  from  which 
the  offer  of  the  Government  was  developed,  but  the  committee 
was  apparently  not  responsible  for  the  details  of  the  scheme  for 
the  establishment  of  a  large  Joint-stock  Dye-manufacturing 
Company,  which  was  made  public  on  22nd  December  1914. 

Prior  to  this,  on  roth  December  1914,  a  meeting  of  large 
users  of  dyes  was  held  at  the  Board  of  Trade,  at  which  a  resolu- 
tion was  unanimously  passed  welcoming  the  assistance  of  the 
Government  in  a  national  effort  to  increase  the  British  supply  of 
dyes.  A  small  committee,  representative  only  of  the  users  of 
dyes,  was  appointed,  and  elaborated  the  scheme  to  which  reference 
has  already  been  made  for  the  formation  of  a  manufacturing 
company. 

An  influential  committee,  appointed  by  the  Society  of  Dyers 
and  Colourists,  has  also  made  exhaustive  inquiries  on  the  tech- 
nical side  and  has  accumulated  much  valuable  information. 

It  is  well  known  that  there  are  enormous  difficulties  involved 
in  establishing  on  a  permanent  basis  the  manufacture  of  dyes  on  a 
scale  adequate  to  supply  our  needs,  and  that  without  Government 
or  legislative  assistance  they  might  well  prove  insurmountable  ; 
and  the  action  of  the  Government  in  proffering  such  broad- 
minded  and  generous  support  has  received,  as  it  deserved,  the 
recognition  of  all  parties. 

The  German  colour  industry  is  probably  the  most  compli- 
cated, most  highly  developed,  and  most  profitable  of  all  her  great 
industries.  The  capital  invested  in  it  is  about  .£12,000,000,  and 
the  German  exports  of  dyes  and  associated  products  in  1912 
were  valued  at  £10,600,000.  The  organisation,  both  for  pro- 
duction and  for  marketing  and  distribution,  is  wonderfully 
efficient,  and  above  all  the  Germans  have  long  realised  that  in 
this  branch  of  industry  the  scientific  mind  and  scientific  method 
must  be  predominant,  not  only  in  the  laboratory  and  in  the 
works,  but  in  the  management.  The  boards  of  directors  of  their 
large  works  are  virtually  committees  of  technical  and  commercial 
experts  who  are  in  intimate  touch  with  the  respective  branches  of 


MANUFACTURE  OF  DYESTUFFS  IN  BRITAIN     373 

the  works  of  which  they  have  special  knowledge.  In  a  word, 
the  trained  man  of  science  has  in  these  works  come  to  his  own, 
and  a  proper  recognition  of  the  necessity  of  this  is  vital  to  the 
development  of  the  British  colour  industry. 

The  reasons  for  the  predominance  of  Germany  in  this 
particular  industry  have  been  frequently  and  variously  stated, 
but  it  is  now  generally  conceded  that  there  is  no  lack  of  highly 
trained  chemists  in  this  country  competent  to  build  up  a  com- 
mercially successful  enterprise.  With  regard  to  other  factors, 
we  have,  of  course,  a  superabundance  of  the  coal-tar  products 
which  form  the  basis  of  the  manufacture,  but  the  manufacture 
of  certain  essential  reagents,  e.g.  fuming  sulphuric  acid,  though 
already  existing,  will  have  to  be  greatly  increased. 

Government  assistance  will  be  required  in  regard  to  the 
provision  of  cheap  alcohol,  and  the  resources  and  skill  of  the 
chemical  engineer  will  be  heavily  drawn  upon  to  provide  the 
essential  apparatus.  A  great  number  of  chemists  will  be  needed 
to  work  out  the  details  of  known  processes,  first  on  the  laboratory 
scale,  and  later  on  a  bulk  basis,  and  the  well-equipped  laboratories 
and  staffs  of  the  universities  and  larger  technical  institutions 
might  well  be  pressed  into  service  for  much  of  the  preliminary 
work.  Many  chemists  will  also  be  required  for  developing  new 
processes  and  for  other  research  work,  because  of  no  other  in- 
dustry can  it  be  so  truly  said  that  stagnation  spells  failure. 

The  great  complexity  of  the  manufacture  of  dyestuffs  is  not 
due  to  the  use  of  a  large  number  of  raw  materials,  the  direct 
products  from  coal  tar  being  only  nine  or  ten.  By  chemical 
treatment  these  are,  however,  transformed  into  250  to  300 
different  intermediate  products  which,  in  their  turn,  yield  some 
1 200  chemically  distinct  dyestuffs.  In  some  processes  of  manu- 
facture high  temperatures  and  pressures  are  required  ;  in  others 
the  temperature  must  be  reduced,  and  a  large  refrigerating  plant 
is  an  essential  feature  of  a  colour  works. 

Surely,  then,  it  is  abundantly  evident  that  the  technical  expert 
must  be  the  preponderating  element  in  the  dye  factory,  and  that 
he  must  have  a  large  share  in  the  management  and  control. 
The  British  custom  of  entrusting  the  management  of  large 
concerns  to  financiers,  commercial  magnates,  and  "men  of  affairs" 
has  done  much  to  retard  the  scientific  development  of  our 
industries,  and  the  adequate  representation  of  the  technical  expert 
on  the  directorate  is  vital  to  the  success  of  the  new  scheme. 


374         THE   BRITISH   COAL-TAR   INDUSTRY 

Lord  Moulton  laid  down  three  propositions  with  regard  to 
the  proposed  new  British  dye-manufacturing  company.  It  must 
be  large  enough  to  be  able  to  face  severe  competition  at  the  end 
of  the  war.  It  must  be,  and  must  remain,  entirely  British,  and 
it  must  be  co-operative  ;  and  all  these  conditions  are  fulfilled  by 
the  scheme  put  forward.  It  is  proposed  that  the  share  capital 
shall  be  £3,000,000,  and  the  Government  offers  to  supplement 
this  by  a  loan  of  £1,500,000  at  4  per  cent,  and  repayable  in 
twenty-five  years.  The  four  and  a  half  millions  of  capital  thus 
proposed  is  probably  ample  to  establish  and  develop  an  industry 
which  would  make  us  independent  of  imported  products. 

The  proposals  with  regard  to  co-operation  are  that  dyers  and 
others  associated  with  the  consumption  of  the  products,  e.g. 
spinners,  manufacturers,  merchants,  textile  machinists,  etc., 
should  take  shares  in  the  new  company  and  thus  become 
interested  in  its  success.  This  is  quite  sound  and  receives 
general  acceptance,  but  certain  suggestions  in  the  prospectus  with 
regard  to  a  pro  rata  subscription  appear  to  be  unworkable. 

The  Government  reserves  the  right  of  appointing  two 
directors  of  the  company,  and  it  is  much  to  be  regretted  that  the 
opportunity  has  not  been  taken  of  giving  a  wise  lead  in  regard 
to  the  character  of  the  directorate,  by  stipulating  that  the  scientific 
technologist  should  be  adequately  represented. 

Another  feature  of  the  scheme  propounded  by  the  committee 
is  that  certain  existing  colour  works  are  to  be  taken  over  by  the 
new  company  to  form  the  nucleus  of  development.  The 
resources  of  these  works  are  to  be  extended  as  rapidly  as  possible 
in  order  to  cope  with  immediate  necessities  and  prevent  an  actual 
famine  in  dyewares — in  fact,  large  extensions  are  at  the  present 
moment  being  made. 

A  point  which  presents  some  difficulty  in  adjustment  is  the 
relationship  of  the  new  company  to  existing  British  dye-produc- 
ing firms,  or  such  as  may  be  established  in  the  future.  It  is 
obviously  not  desirable  to  stifle  private  enterprise  by  anything  in 
the  nature  of  a  monopoly  supported  by  the  Government,  but  the 
existence  of  successful  German  firms  which  are  outside  the  two 
great  "  Interessengemeinschafte,"  or  rings,  indicates  that  the 
difficulty  is  more  apparent  than  real.  A  somewhat  cognate 
matter  is  the  future  relationship  of  the  new  company  to  the 
Swiss  firms  which  are  importing  to  us  during  the  present  crisis. 

The  various  criticisms    of    the    Government  schemes  which 


MANUFACTURE  OF  DYESTUFFS  IN  BRITAIN       375 

have  been  offered  refer,  not  to  general  principles,  but  in  almost 
all  cases  to  more  or  less  important  details.  The  general  outline 
of  the  scheme — the  establishment,  by  co-operation  of  those 
specially  concerned,  of  a  new  company  with  great  resources  and 
financially  aided  by  the  Government — has  received  general 
approval,  and  the  unprecedented  step  taken  by  the  Government 
has  been  applauded  by  men  of  all  parties,  as  meeting  an  industrial 
crisis  in  a  bold  and  statesmanlike  manner.  In  response  to  this, 
and  in  recognition  of  a  national  emergency,  it  is  the  obvious  duty 
of  all  who  are  commercially  interested  to  deal  with  the  question 
from  the  national  rather  than  from  the  individual  point  of  view. 
Support  of  a  scheme  for  the  manufacture  in  Britain  of  British- 
used  dyes  is,  at  its  lowest  estimate,  an  essential  business  insurance, 
and  on  a  higher  plane  it  is  helping  forward  a  movement  to  free 
our  great  textile  industry  from  the  danger  of  German  domination. 
Apart  altogether  from  the  commercial  aspect,  there  is,  therefore, 
a  great  obligation  of  patriotism  involved.  The  scheme  put 
forward — possibly  as  a  ballon  d'essai  as  regards  details — certainly 
requires  modification,  but  from  it  can  be  elaborated  a  national 
and  co-operative  effort  which  is  bound  to  succeed.  Let  us  all 
take  as  a  starting-point  of  our  deliberations  that  the  thing  must 
be  done,  and  then  the  details  of  how  to  do  it  will  fall  into  proper 
perspective. 

Finally,  it  may  be  pointed  out  that  incidental  advantages  of 
enormous  national  value  will  accrue  as  the  result  of  the  successful 
fruition  of  this  dyeware  manufacture  scheme.  The  necessity 
for  dealing  with  our  industries  from  a  national,  rather  than  an 
individualistic,  point  of  view  will  be  more  fully  recognised  by  the 
Government  and  by  the  public.  The  necessity  for  the  use  of 
scientific  method  and  control  of  our  industries  will  be  strongly 
emphasised.  The  claims  of  patriotism  and  the  value  of  co- 
operation in  commercial  matters  will  receive  fuller  consideration. 
And  lastly,  the  establishment  of  a  powerful  company  for  the 
manufacture  of  organic  dyestuffs  will  afford  protection  to  our 
great  industries  concerned  in  the  manufacture  of  inorganic 
chemicals,  an  attack  on  which  was  beginning  to  be  organised. 

Now  is  our  opportunity,  and  everything  is  propitious. 
Patriotism  and  self-interest  are  alike  clamouring  for  the  establish- 
ment of  a  large  dye-manufacturing  concern,  and  the  Government 
offers  its  support.  One  essential  thing  may,  however,  be  over- 
looked— the  new  company  is  foredoomed  to  failure  unless  a 


376         THE   BRITISH   COAL-TAR   INDUSTRY 

scientific  rather  than  a  purely  commercial  spirit  permeates  the 
management,  and  an  appeal  is  made  to  the  Government  and  to 
the  eminent  business  men  forming  the  committee  who  have 
issued  the  scheme  that  in  its  final  form  it  may  include  a  full 
recognition  of  this  fundamental  point. 


II 

THE  GOVERNMENT'S  MODIFIED  SCHEME 
(Nature^  25th  February  1915,  p.  700) 

The  discussion  on  the  various  aspects  of  the  problem  of  pro- 
ducing in  this  country  an  adequate  supply  of  dyestuffs  proceeds 
without  intermission.  The  question  has  for  some  time  assumed 
a  national  aspect  and  has  been  the  subject  of  Parliamentary  debate 
or  question  on  at  least  three  occasions.  It  has  also  been  debated 
at  meetings  of  the  Chambers  of  Commerce  in  the  chief  industrial 
centres,  and  people  most  directly  interested  have  had  many 
opportunities  of  expressing  their  opinions  at  meetings  of  their 
various  organisations,  or  at  gatherings  specially  convened  for 
the  purpose. 

To  a  great  extent  the  discussions  have  centred  round  the 
adequacy  and  equity  of  the  commercial  proposals  involved  in 
the  official  scheme  now  before  the  public.  These  have  received 
much  more  general  acceptance  than  those  put  forward  in  the 
first  scheme,  and  it  appears  probable  that  the  committee  has  now 
received  promises  of  support  to  an  amount  representing  a 
substantial  proportion  of  the  initial  capital  proposed  for  the 
new  company. 

The  members  of  the  committee  themselves  admit  that  it  is 
an  easy  matter  to  criticise  the  scheme  adversely,  and  it  is 
obviously  impossible  to  devise  a  solution  of  the  problem 
satisfactory  to  all  minds. 

If  the  matter  is  to  be  viewed  as  an  ordinary  commercial 
proposition,  if  questions  of  free  trade  or  protection  are  to  be 
taken  into  account,  or  if  early  dividends  are  to  be  assured,  then 
any  scheme  which  might  be  put  forward  could  be  shown  to  be 
unworthy  of  support.  But  whilst  criticism  on  these  lines  has 
been  plentiful,  there  has  latterly  been  a  rally  of  support  by  those 
taking  broader  views — a  support  which  has  probably  been  largely 
induced  by  a  sense  of  national  need,  and  has  certainly  been 


MANUFACTURE  OF  DYESTUFFS  IN  BRITAIN       377 

greatly  developed  by  the  action  of  the  Government  in  offering 
to  endow  the  research  work  which  is  essential  to  the  extent  of 
;£  1 00,000.  This  action  has  engendered  a  feeling  of  confidence 
that  the  Government  will  take  any  further  steps  which  the  future 
may  show  to  be  vital  to  the  success  of  the  British  dye- 
manufacturing  industry. 

It  is  to  be  hoped  that  the  committee  in  charge  of  the  scheme 
will  shortly  be  able  to  announce  the  results  of  its  inquiries,  and 
that  these  will  show  that  the  great  textile  trade  of  the  country 
has  responded  adequately.  In  the  meantime,  the  arrangements 
for  carrying  out  the  necessary  preliminary  chemical  work  should 
be  proceeded  with. 

A  Mobilisation  of  Chemists 

Speaking  in  Bradford  on  8th  February,  the  present  writer 
advocated  immediate  action  by  the  Government  or  the  Board 
of  Trade  Advisory  Committee  in  the  direction  of  utilising  the 
services  of  British  chemists.  There  is  on  one  hand  a  large 
amount  of  chemical  work  to  be  done  before  the  industry  can 
be  greatly  developed,  and  on  the  other  there  are  a  great  number 
of  well-staffed  and  well-equipped  laboratories  in  our  universities 
and  technical  colleges  which  might  render  great  service  to  the 
industry.  To  avoid  wasteful  duplication  of  work  and  to  co- 
ordinate the  results,  it  is  essential  that  some  organised  scheme 
and  allotment  of  work  should  be  arranged,  and  it  is  suggested 
that  a  conference  of  those  concerned  should  be  held  at  an  early 
date  to  formulate  such  a  scheme.  Even  if  to-morrow  the  whole 
of  the  available  chemical  force  set  to  work  on  some  organised 
plan,  it  would  not  be  any  too  soon  to  get  the  necessary  informa- 
tion together  for  the  use  of  the  existing  works  and  the  new 
works  when  they  are  started. 

The  urgency  of  this  action  is  further  shown  by  a  resolution 
passed  by  an  important  meeting  held  in  Manchester  on  i6th 
February,  which  was  presided  over  by  Sir  Charles  Macara. 
The  resolution,  which  was  carried  unanimously,  stated  :  "That 
in  the  opinion  of  this  meeting  the  Government  would  do  well 
to  organise  immediately  the  present  chemical  talent  in  the 
country  with  a  view  to  chemical  research  being  undertaken 
for,  and  on  behalf  of,  all  manufacturers  interested,  and  that 
the  services  of  these  experts  should  be  available  for  all  desirous 
of  availing  themselves  thereof.'* 


378         THE   BRITISH   COAL-TAR   INDUSTRY 

The  adoption  of  such  a  plan  for  bringing  the  educational 
institutions  more  closely  into  touch  with  the  industries  would 
in  all  probability  mark  the  beginning  of  a  new  era  in  which  both 
would  benefit.  The  more  intimate  association  of  professors  of 
chemistry  with  chemical  industry  would  introduce  into  the  works 
that  higher  ideal  and  broader  scientific  spirit  upon  which  successful 
research  and  development  depend,  whilst  the  schools  would 
benefit  by  the  great  incentive  of  practical  reality. 


XXIX.:    1915 
THE  CHEMICAL  INDUSTRIES  OF   GERMANY 

BY  PROFESSOR  P.  FRANKLAND,  F.R.S. 
[Abstract] 

(Nature,  nth  March  1915,  p.  47;   Journal  of  the  Society  of  Chemical 
Industry^  April  1915,  p.  307) 

THE  interest  and  importance  of  the  subject  at  the  present  time 
are  sufficiently  obvious.  In  outlining  some  of  the  origins  of 
chemical  industry  in  Germany,  the  lecturer  pointed  out  how  the 
royal  house  of  Prussia  had  been  frequently  associated  with 
chemical  enterprise.  The  Markgrave  John  was  actually  sur- 
named  "  the  Alchemist "  ;  the  Great  Elector  was  a  patron  of 
chemistry  and  provided  a  laboratory  at  Potsdam  for  the  celebrated 
Kunkel,  one  of  the  first  to  discover  phosphorus,  and  who  also 
effected  great  advances  in  the  manufacture  of  glass.  Frederick 
the  Great  established  the  Royal  Berlin  porcelain  factory,  which 
still  occupies  some  of  the  original  premises.  In  the  same  reign 
also  the  chemist  Marggraf  made  those  classical  investigations  on 
the  occurrence  of  sugar  in  the  vegetable  kingdom  which  later  led 
to  the  foundation  of  the  beet-sugar  industry,  which  was  initially 
subsidised  by  Frederick  William  III.,  the  founder  of  the  Uni- 
versity of  Berlin  in  1809.  (^n  I9I4>  tne  Berlin  University  had 
12,585  students,  and  received  an  annual  grant  from  the  State  of 
more  than  £200,000.) 

Great  industries  have  developed  out  of  these  early  steps. 
From  the  discovery  of  phosphorus  came  the  match  industry. 
The  German  annual  production  of  matches  is  £4,600,000  ;  the 
British  production  in  1907  amounted  to  £775,000,  whilst  the 
British  consumption  in  1910  was  estimated  at  £1,300,000. 
Again,  the  porcelain  and  pottery  manufacture  had  attained  great 
dimensions  in  Germany,  the  exports  in  1912  amounting  to 

379 


380         THE   BRITISH   COAL-TAR    INDUSTRY 

£3,556,000,  whilst  the  glass  industry  was  even  on  a  larger  scale, 
the  recent  annual  exports  being  more  than  £7,000,000.  Great 
inconvenience  in  connection  with  all  scientific  work  is  at  present 
being  experienced  through  the  absence  of  German  glass.  The 
important  cyanide  industry  may  be  said  to  have  taken  its  origin 
from  the  accidental  discovery  by  Diesbach,  of  Berlin,  of  Prussian 
blue  in  the  first  decade  of  the  eighteenth  century.  Germany's 
annual  production  of  cyanides  is  now  estimated  at  10,000  tons 
(£650,000),  or  about  one-half  of  the  world's  production. 

The  beet-sugar  industry  exemplifies  how  agricultural  pro- 
duction can  be  improved  by  systematic  research  such  as  has  been 
bestowed  on  it  by  Germany  ;  thus  : — 

In  1840  100  Ib.  of  beet  yielded  5*9  Ib.  sugar. 

1850       „  „  „  7-3 

1870       „  „  „  8-4 

1890       „  „  „  12-5 

1910       „  „  „  15-8 

Again,  in 

1871  mean  yield  of  beet  per  hectare  of  land  was  246  quintals. 
19!°  >i  »  »  3°° 

And  again,  in  the  economy  of  manufacture 

In  1867  coal  used  on  100  Ib.  beet  .         .         .         .     35  Ib. 

1877         »  ...     24  „ 

1890         „             „             „  .     10  „ 

19°°         »             »             »  -7  » 

The  former  supremacy  of  Great  Britain  in  the  manufacture 
of  the  common  chemicals — sulphuric  acid  and  soda — was  referred 
to  and  compared  with  the  production  of  these  materials  in  1910. 

PRODUCTION  IN  TONS,  1910 

Germany.          England.       France.      United  States.       World. 

Sulphuric  acid  .  1,250,000  1,000,000  500,000  1,200,000  5,000,000 
Soda  .  .  .  400,000  700,000  200,000  250,000  2,000,000 

The  substitution  of  the  ammonia-soda  for  the  earlier  Le  Blanc 
soda  process,  and  of  the  contact  for  the  time-honoured  leaden 
chamber  process  of  sulphuric  acid  manufacture,  had  no  doubt 
greatly  assisted  both  Germany  and  America  in  becoming  inde- 
pendent of  the  British  manufacture  of  these  chemicals. 

During  the  past  twenty-five  years  the  manufacture  of  chlo- 
rine and  caustic  soda  by  the  electrolysis  of  common  salt  (sodium 
chloride)  has  been  realised  and  rapidly  extended.  This  process 


THE  CHEMICAL  INDUSTRIES  OF  GERMANY     381 

is  carried  out  on  a  very  large  scale  in  Germany,  where  extensive 
use  is  made  of  liquefied  chlorine.  The  production  of  electrolytic 
chlorine  is  attended  with  the  simultaneous  evolution  of  large 
quantities  of  hydrogen  gas  for  which  uses  have  been  found; 
thus,  for  filling  the  dirigible  balloons  upon  which  such  hopes  of 
conquest  have  been  based  by  Germany,  whilst  in  the  oxyhydrogen 
flame  it  has  been  employed  for  welding,  for  the  cutting  even  of 
thick  iron  structures,  and  for  the  manufacture  of  artificial  gems. 
The  artificial  production  of  gems — corundum,  ruby,  sapphire, 
etc.  —  was  discovered  in  France  by  Michaud,  Verneuil,  and 
Paquier,  and  has  been  greatly  taken  up  by  the  Elektrochemische 
Werke  at  Bitterfeld,  in  Germany.  More  than  a  ton  of  these 
gems,  which  are  identical  in  chemical  composition  with  the  natural 
gems,  are  said  to  be  annually  produced.  Other  more  important 
uses  for  hydrogen  have  been  found  for  the  hardening  of  fats,  and 
still  more  recently  for  the  synthetic  production  of  ammonia  to  be 
presently  referred  to,  and  which  is  an  industrial  achievement  of 
the  first  magnitude.  Cheaper  sources  of  hydrogen  than  the 
electrolytic  method  have  been  introduced,  and  notably  that  de- 
pending on  the  production  of  water-gas  (consisting  of  equal 
volumes  of  hydrogen  and  carbon  monoxide)  from  steam  and 
coke  at  a  red  heat,  the  carbon  monoxide  being  subsequently 
separated  from  the  hydrogen  by  liquefying  it  by  means  of  the 
low-temperature  apparatus  of  Carl  von  Linde,  of  Munich. 

AMMONIA,  NITRATES,  AND  FIXATION  OF  FREE  NITROGEN 

As  is  well  known,  one  of  the  most  important  problems  at 
the  present  time  is  to  provide  the  world  with  nitrate  when  the 
deposits  in  Chile  shall  have  been  exhausted.  The  problem  is 
bound  up  with  the  still  wider  one  of  the  fixation  of  atmospheric 
nitrogen.  This  again,  as  is  well  known,  is  now  accomplished  on 
a  large  scale  by  the  production  of  nitric  acid  from  atmospheric 
nitrogen  and  oxygen  by  means  of  the  electric  furnace  of  Birkeland 
and  Eyde,  or  by  the  production  of  calcium  cyanamide  by  passing 
atmospheric  nitrogen  over  heated  calcium  carbide.  Both  these 
processes  involve  the  use  of  the  electric  furnace,  in  the  former 
for  effecting  the  union  of  the  nitrogen  and  oxygen,  and  in  the 
latter  for  the  preliminary  production  of  the  calcium  carbide. 
Abundant  water-power  being  necessary  for  the  economic  opera- 
tion of  the  above  processes,  Norway  has  become  their  chief  centre, 


382         THE   BRITISH   COAL-TAR   INDUSTRY 

whilst  Germany  has  sought  other  means  of  nitrogen-fixation  which 
could  be  carried  on  within  her  own  territories.  The  synthesis  of 
ammonia  from  hydrogen  and  atmospheric  nitrogen  under  a  pressure 
of  200  atmospheres  and  at  500°  C.  in  the  presence  of  a  catalyst, 
has  been  successfully  worked  out  by  Haber  in  conjunction  with 
the  Badische  Anil  in-  und  Soda-Fabrik,  and  a  plant  capable  of 
yielding  130,000  tons  of  sulphate  of  ammonia  per  annum  was  to 
have  been  ready  in  1915.  The  second  step  in  the  German  pro- 
gramme was  to  convert  the  ammonia  into  nitric  acid  by  burning 
it  in  air  in  the  presence  of  a  catalyst.  In  this  way  it  is  hoped  to 
make  Germany  independent  of  foreign  countries  for  the  nitrate 
required  in  the  manufacture  of  explosives.  It  is  asserted  that 
this  independence  Germany  has  actually  secured  at  the  present 
moment. 

EXPLOSIVES 

Of  the  modern  high  explosives,  gun-cotton  was  discovered 
by  Schoenbein  and  by  Boettger  in  1846.  The  manufacture  of 
nitroglycerine  (discovered  by  Sobrero  in  Paris  in  1847)  was 
first  realised  by  the  Swede,  Alfred  Nobel,  in  1862,  and  it  was 
Nobel  who  first  adapted  these  powerful  explosives  for  ballistic 
purposes.  Trinitrotoluene,  of  which  so  much  has  been  heard 
recently,  was  first  proposed  for  filling  shells  by  Haessermann  in 
1891.  It  is  said  to  be  surpassed,  both  as  regards  safety  and 
disruptive  effect,  by  tetranitro-aniline  discovered  in  England  by 
Dr  Fluerscheim.  The  great  magnitude  of  the  German  explosives 
industry  is  seen  from  the  following  figures  : — 

Tons. 

Total  German  production  of  explosives  .         .         .         .     40,000 
or  about  one-tenth  of  the  estimated  world  production. 

Germany  exported  in  1908  to  the  value  of      .         .     £1, 000,000 
1912     „  „  3,000,000 

ARTIFICIAL  SILK 

This  remarkable  industry,  originated  by  Count  Chardonnet 
in  France  in  1891,  has  also  been  largely  developed  on  German 
soil.  The  German  production  amounts  to  about  2000  tons 
annually  (£1,200,000)  out  of  a  total  world  production  of  about 
7000  tons.  French,  German,  and  British  patents  have  largely 
contributed  to  the  success  of  this  industry. 


THE  CHEMICAL  INDUSTRIES  OF  GERMANY     383 

INDUSTRIES  DEPENDENT  ON  SYNTHETIC  ORGANIC  CHEMISTRY 

It  is  in  respect  of  these  industries  that  the  world  is  learning 
that  Germany  holds  the  undisputed  supremacy.  It  is  in  Germany 
alone  that  manufacturers  have  been  found  prepared  to  embark 
their  capital  and  undertake  industrial  enterprises  of  the  first 
magnitude  on  the  advice  of  the  organic  chemist.  The  success 
which  has  been  achieved  by  the  German  manufacturers  of  artificial 
dyestuffs,  drugs,  and  perfumes,  and  the  hegemony  which  they 
have  secured  in  this  branch  of  industry,  has  been  the  frequent 
subject  of  warning  by  professors  of  chemistry  in  this  country  for 
upwards  of  a  generation.  The  seriousness  of  the  situation  which 
has  arisen  through  the  neglect  of  those  warnings  is  seen  from  the 
following  figures  : — 

Annual  value  of  dyestuffs  used  in  Britain  ....  ^£2, 000,000 

„               trade  in  which  these  dyes  are  employed   .  200,000,000 

Workmen  dependent  on  this  trade,  1,500,000 

Total  value  of  dyestuffs  imported  (1913)  into  Britain         .  1,892,055 

„                 ,,                 „            from  Germany       .         .  1,730,821 

Less  than  one-tenth  of  the  annual  value  of  the  dyestuffs 
consumed  in  England  is  produced  in  this  country.  Thus,  by 
controlling  the  dyestuff  industry,  Germany  indirectly  holds  in 
her  grip  the  whole  of  the  textile  industry. 

Much  inconvenience  has  been  experienced  also  in  the  shortage 
of  artificial  drugs  and  consequent  high  prices,  more  especially  at 
the  beginning  of  the  war,  as  even  the  simplest  of  these  products 
were  almost  exclusively  made  in  Germany.  The  manufacture  of 
some  of  these  is,  however,  now  being  successfully  carried  on  in 
England. 

Again,  the  shortage  of  organic  chemicals  required  for  research 
purposes,  which  practically  all  come  from  Germany,  is  occasioning 
most  serious  difficulties  in  our  university  laboratories. 

For  the  manufacture  of  dyestuffs  and  similar  synthetic  pro- 
ducts Germany  was  formerly  largely  dependent  on  England 
for  the  raw  material — coal-tar.  But  in  this  case,  again,  the 
ambition  of  Germany  to  become  in  all  respects  independent  and 
self-contained  has  led  her  in  recent  years  to  make  the  most 
strenuous  efforts  to  recover  the  maximum  amount  of  coal-tar 
both  from  the  manufacture  of  gas  and  from  coke-ovens,  which 
endeavour  has  been  assisted  by  the  enormous  growth  in  her  iron 
and  steel  industries.  Thus  in  1897  Germany  obtained  only 


384         THE   BRITISH   COAL-TAR   INDUSTRY 

52,000  tons  of  coal-tar  from  coke-ovens,  whilst  in  1908  she 
obtained  no  fewer  than  632,400  tons  from  that  source,  besides 
300,000  tons  from  the  manufacture  of  gas.  Thus  at  the  present 
time  the  German  output  of  coal-tar  about  equals,  if  it  does  not 
exceed,  that  of  England. 

The  German  production  of  artificial  perfumes  is  said  to 
amount  to  a  value  of  about  £2,500,000  annually.  In  this 
department  of  applied  chemistry,  again,  one  of  the  first  steps 
was  made  by  the  late  Sir  William  Perkin,  by  the  synthesis  in 
1868  of  coumarin,  the  much-valued  odoriferous  principle  of 
woodruff  {Asperula  odorata]. 

The  effect  of  artificial  synthesis  on  the  price  of  natural 
perfumes  may  be  gathered  from  the  following  examples  : — 


Price  of  I  kilo. 

Natural. 

Synthetic. 

Coumarin       .... 
Vanillin          .... 
Heliotropin    .... 

£ 

25 
5° 

£   s.    d. 
i     5     o 

I     IO       O 
IO       0 

The  proposal  of  the  Government  to  assist  the  British  coal-tar 
colour  industry  is  being  watched  with  the  greatest  interest  both 
by  manufacturers  and  chemists.  The  problem  of  relieving  the 
immediate  shortage  during  the  war  must  be  carefully  distin- 
guished from  the  later  problem  of  securing  the  independence 
of  the  home  industry  after  the  war  by  greatly  increasing  the 
British  output.  The  realisation  of  the  latter  object  will  be 
attended  with  the  greatest  possible  difficulty.  The  industry  will 
require  "  nursing "  for  a  great  many  years.  The  undertaking 
must  be  possessed  of  such  elasticity  that  it  can  ramify  into  other 
branches  of  chemical  or  other  industry  whenever  advantageous 
opportunities  arise  for  such  departures. 

The  great  magnitude  of  the  German  coal-tar  colour  industry 
may  be  gathered  from  the  fact  that  the  two  groups  into  which 
the  principal  firms  are  associated  have  at  the  present  time  a  total 
share  capital  of  about  £12,000,000,  on  which  a  dividend  of  about 
28  per  cent,  is  paid.  In  1912  Germany  produced  dyestuffs  to 
the  value  of  £12,500,000,  of  which  to  the  value  of  £10,000,000 
were  exported. 


THE  CHEMICAL  INDUSTRIES  OF  GERMANY     385 

The  above  facts  speak  for  themselves  and  proclaim  in  the 
most  convincing  manner  the  stupendous  progress  which  has  been 
made  by  Germany  in  the  chemical  industries  during  the  past 
forty  years.  It  is  equally  certain  that  England,  once  pre-eminent 
for  chemical  manufactures,  has  not  progressed  at  the  same  rate  and 
is  at  the  present  moment  suffering  much  inconvenience  through 
being  so  largely  dependent  on  German  chemical  products  of  one 
kind  and  another.  The  country  is  now  reaping  the  harvest  of 
humiliation  which  it  has  sown  for  itself  in  spite  of  the  warnings 
repeated  ad  nauseam  during  a  whole  generation.  The  systematic 
neglect  of  chemical  science  and  the  failure  by  manufacturers  to 
utilise  the  services  of  highly  qualified  chemists,  could  only  lead  to 
the  result  that  all  the  industries  which  are  dependent  on  a  pro- 
found knowledge  of  chemistry  should  tend  to  disappear  from  our 
midst  and  pass  into  the  hands  of  those  who  are  prepared,  not  only 
to  apply  new  chemical  discoveries  to  industry,  but  even  to  prose- 
cute the  most  varied  chemical  investigations  in  the  hope  of  sooner 
or  later  making  discoveries  which  shall  be  of  advantage  to  their 
commercial  undertakings.  The  mischief  caused  through  the  neg- 
lect of  chemistry  by  practical  men  in  this  country  has  been  so  subtle 
that  to  a  large  extent  it  has  remained  concealed  from  the  average 
man  of  intelligence  and  from  the  governmental  classes.  During 
the  past  forty  years  our  country  has  been  accumulating  wealth 
in  an  altogether  unprecedented  fashion,  so  that  the  loss  or 
restriction  of  some  industries  appeared  a  matter  of  no  importance 
to  political  observers  taking  only  a  broad  and  superficial  survey 
of  the  national  resources.  The  whole  of  our  arrangements  have 
evolved  during  the  past  half-century  on  the  assumption  that  this 
country  would  never  again  be  engaged  in  a  European  war,  whilst 
still  more  recently  the  new  democracy  has  vainly  boasted  that 
it  could  prevent  such  a  war  by  means  of  a  general  strike.  The 
year  1914  has  seen  the  dissolution  of  many  fools'  paradises 
and  has  given  the  coup  de  grace  to  all  these  vain  imaginings,  with 
the  result  that  we  find  our  vast  textile  industry  in  serious  peril 
because  the  much  smaller  dyestuff  industry  has  been  complacently 
allowed  to  slide  into  the  hands  of  our  sagacious  and  more  pains- 
taking enemies.  The  same  carelessness  and  want  of  foresight 
had  even  allowed  us  to  become  dependent  on  Germany  for  some 
of  the  most  important  materials  used  as  explosives,  e.g.  trinitro- 
toluene, and  for  many  of  the  most  valued  drugs  required  alike 
by  our  Army,  Navy,  and  civil  population. 

25 


386         THE   BRITISH   COAL-TAR   INDUSTRY 

The  complete  breakdown  in  our  supply  of  fine  chemicals, 
which  is  the  direct  outcome  of  the  disregard  of  the  constant 
warnings  emitted  by  scores  of  British  chemists,  has  led  the 
Government  of  the  day  to  intervene  and  attempt  to  remedy 
the  intolerable  state  of  affairs  which  has  arisen  in  connection  with 
the  supply  of  coal-tar  colours. 

We  devoutly  hope  that   success  will  attend  the  endeavour 
to  establish  the  coal-tar  colour  industry  in  these  Islands  on  the 
largest  possible  scale.     Whatever  the  ultimate  scheme  adopted 
may  be,  I  would  venture  to  point  out  that  it  must  be  based  on 
a  clear  understanding  of  the  following  considerations  :  (i)  That 
the  provision  of  the  required  chemicals  during  the  continuance  of 
the  war  is  one  thing,  and  that  their  production  on  a  commercial 
basis  after  the  cessation   of  hostilities  is  quite  another  matter. 
(2)  It  appears  to  me  that  in  order  to  provide  the  needful  supply 
during  the  war,  the  only  reasonable  course  is  to  assist  in  every 
possible  way  those  firms  which  are  already  making  similar  or 
closely  allied  products  so  as  to  enable  them   to  produce  their 
present  goods  on  a  larger  scale,  and  as  far  as  practicable  to 
undertake   the  manufacture    of   others  which  are   urgently  re- 
quired.    The  immediate  problem  will  be  also  greatly  facilitated 
by  utilising  supplies  obtainable  from  neutral  powers,  and  more 
especially  from   Switzerland,  which  is  the  only  country,  other 
than  Germany,  in  which  the  manufacture  of  dyestuffs  and  similar 
chemical  products  has  been  vigorously  prosecuted.    (3)  As  regards 
the  prospects  of  the  home  industry  after  the  war,  it  will  require 
"  nursing."     I  use  the  term  advisedly  in  order  to  obviate  the 
employment  of  another  and  much  more  familiar  one  which  is  so 
dear  to  some  politicians  and  so  hated  by  others  ;  it  will  require 
nursing  for  a  much  longer  period  of  time  than  has  hitherto  been 
mentioned.     In  this  connection  I  would  point  out  that  the  sum 
of  £  1 0,000  a  year  for  ten  years,  which  it  has  been  proposed  to 
guarantee  for  research  purposes,  is  absurdly  inadequate.     (4)  If 
the  industry  is  to  prosper  it  will  not  only  have  to  manufacture 
materials  already  known,  but  also  continually  to  be  introduing 
new  products  of  its  own  discovery,  as  well  as  constantly  to  be 
seeking  to  produce  more  economically  a  great  number  of  auxiliary 
chemicals  required  in  the  manufacturing  processes.     It  is  also 
essential   that   the    undertaking    should    branch    out    into    the 
manufacture    of    other    materials    as    occasion    may   arise   for 
advantageously    utilising    by-products.      (5)    The   competition 


THE  CHEMICAL  INDUSTRIES  OF  GERMANY     387 

which  the  industry  will  have  to  suffer  from  Germany  is  likely 
to  be  much  more  serious  than  is  generally  supposed,  because  it 
must  be  remembered  that  England  only  takes,  as  we  have  seen, 
about  one-fifth  of  the  total  German  exports  of  dyestuffs,  so  that 
it  would  be  comparatively  easy  for  German  firms  specially  to 
reduce  the  price  of  the  goods  sent  to  England.  They  have 
already  done  this  in  America  when  attempts  have  been  made  to 
start  a  dyestuff  industry  there.  It  is  particularly  significant,  and 
augurs  ill  for  the  prospects  of  this  scheme  to  rehabilitate  the 
coal-tar  colour  industry,  that  the  latter  has  failed  to  flourish 
anywhere  excepting  on  German  soil,  and  that  countries  with 
fiscal  systems  entirely  different  from  our  own  have  been  no  more 
successful  in  this  respect  than  have  we  ourselves.  (6)  It  will 
certainly  be  necessary  that  expert  chemical  knowledge  should 
in  the  future  be  much  more  highly  remunerated  than  it  has  been 
in  the  past,  otherwise  the  supply  of  able  and  properly  qualified 
men  will  not  be  forthcoming.  The  flow  of  men  of  high-grade 
intelligence  into  a  profession  is  determined  by  the  prizes  which 
the  profession  has  to  offer,  in  the  form  of  money  and  social 
position.  Consider  the  great  stream  of  able  men  who  are  attracted 
to  the  English  Bar,  in  which  profession  the  prizes,  although 
limited  in  number,  are  of  the  most  substantial  kind,  with  the 
result  that  the  successful  leaders  are  selected  by  the  fiercest 
competition  in  a  very  wide  field.  If  there  is  to  be  a  large  influx 
of  high  intelligence  into  the  chemical  profession,  it  will  be 
necessary  that  there  should  be  some  very  different  prizes  from 
the  paltry  bait  which  is  offered  at  the  present  time,  for  the  study 
of  chemistry  in  this  country  now  only  draws  those  men  who 
either  have  or  think  they  have  an  overpowering  zeal  and  passion 
for  the  science,  to  which  they  devote  themselves  against  the 
advice  of  their  friends.  Notwithstanding  the  absence  of  material 
inducements,  I  venture  to  say  without  fear  of  contradiction  that 
there  is  more  original  investigation  being  prosecuted  in  this 
country  by  chemists  than  by  any  other  body  of  British  men  of 
science,  and  this  I  attribute  to  the  fact  that  such  a  large  proportion 
of  our  number  have  either  been  at  German  Universities  or  are 
the  pupils  of  those  who  have  been  at  these  centres  of  research. 
Nor  are  any  of  us,  I  am  sure,  even  during  this  unfortunate  crisis, 
unmindful  of  the  hospitality  and  the  inspiration  which  we  have 
received  in  the  schools  of  the  enemy.  (7)  If  the  proposed  under- 
taking is  to  succeed,  real  chemists  must  be  on  the  directorate, 


388         THE   BRITISH   COAL-TAR   INDUSTRY 

and  in  a  sufficient  proportion  to  give  effect  to  their  views.  Many 
men  of  science  are  excellent  business  men.  What  does  experience 
teach  in  the  case  of  flourishing  chemical  industries  which  we  for- 
tunately still  have  amongst  us  ?  What  does  not  the  firm  of 
Messrs  Brunner,  Mond  &  Co.,  for  example,  owe  to  the  late  Dr 
Ludwig  Mond,  F.R.S.  ?  (8)  In  attempting  to  establish  a  com- 
mercially successful  coal-tar  colour  company  on  a  large  scale  in  this 
country,  I  venture  to  think  that  the  Government  have  undertaken 
a  task  which  they  will  find  to  be  surrounded  with  difficulties  of 
quite  a  different  order  from  those  which  they  have  had  to 
encounter  in  some  of  their  most  striking  previous  legislative  acts, 
such  as  the  provision  of  salaries  for  members  of  Parliament,  the 
granting  of  old-age  pensions,  and  the  establishment  of  a  compul- 
sory system  of  insurance.  These  are  matters  in  which  if  the 
Government  dictate  we  are  obliged  to  obey  ;  but  the  commercial 
success  of  an  industry  which  is  based  upon  progressive  scientific 
investigation  depends  upon  factors  so  subtle  and  elusive  that 
they  cannot  be  coerced  even  by  a  majority  of  the  House  of 
Commons.  (9)  If  the  chemical  industries  are  to  be  rehabilitated 
in  this  country,  there  must  be  a  complete  change  in  the  attitude 
of  mind  towards  science  in  general,  and  towards  chemical  science 
in  particular,  amongst  the  influential  classes  of  the  population, 
and  it  will  certainly  not  be  effected  by  following  the  precept 
"  Business  as  usual,"  but  by  pursuing  a  policy  which  is  the 
exact  opposite  of  what  is  implied  by  that  phrase. 


XXX.:    1915 

PATENT    LAW    REFORM 
BY  J.  W.  GORDON,  K.C. 

(Journal  of  the  Royal  Society  of  Arts,  I2th  March  1915,  p.  356) 

(THE  first  portion  of  the  paper  gives  a  very  interesting  summary  of  the 
development  of  technical  education  in  England  and  in  Germany?) 

In  the  year  1867  all  the  world  was  looking  admiringly  upon 
the  high  development  and  great  prosperity  of  British  industry. 
Just  as  we  to-day  speak  with  respect  of  the  technical  educational 
institutions  of  America,  France,  Switzerland,  and  Germany,  so  in 
1867  those  other  countries  were  speaking  with  the  like  respect  of 
our  widely  diffused  mechanics'  institutes  and  art  schools.  Sir 
Bernhard  Samuelson,  who  was  in  personal  contact  with  our 
industrial  neighbours  while  at  the  same  time  he  was  an  enterprising 
industrial  captain  himself  in  this  country,  was  by  no  means 
satisfied  that  these  developments,  which  attracted  the  favourable 
notice  of  our  neighbours,  were  sufficient  to  do  justice  to  our- 
selves. At  great  personal  trouble  and  expense  he  produced  a 
report  of  which  Mr  Mundella,  the  Minister  for  Education,  in 
1 88 1  spoke  in  high  praise,  as  a  State  document.  In  1882  Sir 
B.  Samuelson  became  the  Chairman  of  the  Royal  Commission 
known  as  the  Duke  of  Devonshire's  Commission.  In  1897  the 
same  Commission  produced  a  second  report,  in  which  the  further 
development  of  the  technical  education  and  institutions  of 
Germany  was  made  the  subject  of  comparison  with  the  past  and 
with  our  then  existing  system.  The  appearance  of  the  second 
report  of  the  Commission  gave  rise  to  an  important  newspaper 
discussion  which  furnished  the  occasion  for  a  very  remarkable 
utterance  by  Sir  Bernhard  Samuelson,  in  a  short  letter  which 
appeared  in  the  Times  of  25th  January  1897,  and  runs  as 
follows  : — 

389 


390         THE   BRITISH   COAL-TAR   INDUSTRY 

"In  your  leader  on  the  report  of  my  late  colleagues  on 
technical  progress  in  Germany,  you  refer  to  the  fact  that  the 
production  of  dyes  from  coal  tar,  in  which  we  have  been  so 
completely  distanced  by  the  Germans,  was  originated  by  Dr 
Perkin,  and,  it  might  be  added,  by  Dr  Hofmann,  in  this  country. 

"  It  is  not  generally  known  that  we  lost  this  manufacture 
because  the  trade  in  England  was  shut  up  for  fourteen  years  by 
a  master  patent  whilst  no  controlling  patent  had  been  sanctioned 
in  Germany,  so  that  anyone  could  take  up  the  manufacture  there ; 
the  result  being,  of  course,  development  abroad  in  place  of 
stagnation  at  home. 

"  At  the  present  time  we  in  this  country  are  handicapped  as 
much  as  before,  but  from  an  opposition  (sic)  of  things.  The 
Germans,  having  taken  the  lead  with  their  acquired  experience 
and  large  capital,  keep  it  by  patenting  their  new  processes  in  this 
country,  but  carry  out  their  manufacture  abroad.  So  long  as 
they  keep  our  market  supplied,  which  they  take  care  to  do, 
nobody  is  at  liberty  to  make  the  patented  articles  here." 

The  case  to  which  allusion  was  made  in  the  last  paragraph 
was  an  action  tried  in  our  own  courts  in  1883,  anc^  brought 
by  the  Badische  Chemical  Factory  against  Levinstein  &  Co., 
a  firm  of  dye  manufacturers  in  Manchester.  Seldom  has  an 
action  of  greater  practical  importance  been  the  subject  of  pro- 
ceedings in  a  court  of  law. 

The  German  patentees  in  that  case  were  the  inventors  of  a 
dyestuff,  a  chemical  body  having  a  definite  chemical  composition 
and  a  specific  name.  It  may  be  sufficiently  identified  by  speaking 
of  it  as  a  sulpho  acid  of  a  coal-tar  product  yielding  red  and  brown 
dyes.  In  respect  of  the  dyestuffs  which  they  were  the  first  to 
produce,  the  German  patentees  obtained  a  British  patent  which 
was  unquestionably  good.  Those  dyestuffs,  however,  were  of 
no  appreciable  commercial  value. 

The  patent  was  taken  out  in  1878,  and  it  was  five  years  later 
that  the  action  against  Levinstein  came  to  trial.  The  patentees 
then  complained  that  a  very  successful  red  dye  which  Levinstein 
manufactured  was  an  infringement  of  their  patent.  In  the  view 
which  the  court  took  of  the  nature  of  the  patent  this  claim  was 
upheld,  and  judgment  accordingly  was  given  in  their  favour.  But 
the  circumstances  were  very  singular,  and  such  as  to  place  the 
court  in  a  difficult  position  when  deciding  upon  the  issue  of  fact. 
It  was  proved  that  the  dye  which  Levinstein  manufactured  could 


PATENT  LAW   REFORM  391 

not  be  produced  by  the  processes  which  the  inventors  had 
described,  indeed  could  not  be  produced  by  any  process  which 
was  known  to  the  inventors.  The  successful  dye,  which  was 
taken  to  answer  to  the  chemical  composition  of  the  patented 
invention,  was  produced  by  a  secret  process,  and  special  arrange- 
ments were  made  for  taking  the  evidence  in  such  a  manner  that 
the  Levinstein  secret  was  not  disclosed  except  confidentially  to 
the  court  and  its  officers.  The  patentee,  therefore,  although  he 
was  allowed  to  restrain  the  second  inventor  from  working  his 
own  invention  in  this  country,  did  not  acquire  a  knowledge  of 
the  nature  of  that  invention.  Thus  the  action  resulted  in  a 
deadlock,  and  the  operation  of  the  patent  law  in  this  case  was 
to  banish  the  manufacture  of  the  patented  dye  from  this  country 
altogether.  The  patentee  could  not  make  it  because  he  did  not 
know  how,  the  real  inventor  could  not  make  it  because  he  was 
restrained  by  an  injunction  of  the  court.  So  it  happened  that 
by  this  perverse  operation  of  the  patent  law  a  patent,  which  had 
been  granted  with  the  avowed  object  of  introducing  into  this 
country  the  manufacture  of  the  sulpho-acid  dyestuffs,  operated 
to  prevent  their  introduction.  In  the  end  the  manufacture  was 
carried  on  in  Holland,  where  the  German  patentees  had  been 
unable  to  obtain  a  patent.  No  statistics  have  been  published 
from  which  the  value  of  the  dye  industry  which  was  thus  trans- 
ferred to  Holland  can  be  ascertained,  but  credible  information 
goes  to  show  that  the  cloth  sent  from  Manchester  to  Holland  to 
be  dyed  with  Blackley  red  represented  an  industry  which,  in  the 
aggregate,  was  worth  many  millions  of  pounds,  and  Sir  Bernhard 
Samuelson's  warning  is  of  special  importance  at  a  moment  when 
the  investment  of  a  large  sum  of  money  is  in  contemplation  with 
the  object  of  establishing  an  industry  similar  to  that  which  was 
so  ruthlessly  destroyed  by  legal  process  in  1883. 

Now,  in  a  case  like  this  it  is  quite  impossible  to  attribute  the 
loss  of  the  industry  to  any  defect  in  our  system  of  technical 
education.  In  1883  a  Patent  Act  had  been  passed  by  which 
provision  was  made,  among  other  things,  for  the  remedying  of 
the  mischief  which  this  case  illustrates.  It  is  not,  however,  to  be 
supposed  that  the  draftsman  of  that  statute  had  the  facts  of  the 
Levinstein  case  in  mind.  That,  indeed,  was  impossible.  The 
Act  was  passed  in  1883,  and  the  action  was  only  tried  in  that 
year.  The  consequences  of  the  decision  in  that  action  could  not 
possibly  have  been  known  until  a  later  date.  But  although  it 


392         THE   BRITISH   COAL-TAR   INDUSTRY 

had  not  been  illustrated  on  so  large  a  scale,  the  mischief  was 
perfectly  well  known  to  students  of  our  industrial  development 
in  1883.  It  is  not  surprising,  therefore,  to  find  that  an  attempt 
was  made  to  remedy  the  mischief. 

It  has  been  shown  that  the  operation  of  the  patent  law  in 
the  Levinstein  case  was  to  render  the  use  in  this  country  of  a 
valuable  invention  impossible,  and  to  banish  the  resulting  industry 
to  Holland.  It  needs  no  argument  to  show  that  that  is  a 
complete  miscarriage.  The  object  of  the  patent  law  is  to 
facilitate  the  introduction  of  new  manufactures  within  the  realm. 
Whether  we  look  upon  the  patent  as  an  instrument  of  public 
policy,  or  as  a  reward  granted  to  a  meritorious  inventor,  the 
result  from  this  point  of  view  is  the  same.  The  merit  of  the 
inventor  or  the  object  of  the  policy,  as  the  case  may  be,  is  to 
secure  the  advantage  of  an  improvement  in  manufacture  for  the 
benefit  of  the  people  of  this  realm.  In  law,  no  less  than  in 
policy,  the  outcome  of  the  Levinstein  case  was  absurd  and 
lamentable.  How,  then,  could  such  a  result  come  about  ?  The 
answer  to  that  question  is  that  it  came  about  by  the  operation  of 
the  rule  which  makes  an  injunction  by  the  court  the  remedy  for 
an  infringement  of  patent  right. 

In  spite  of  the  stringent  provisions  of  the  Statute  of  Mono- 
polies (1624)  the  injunction  is  to-day  what  it  was  in  the  days  of 
Elizabeth  and  James  I.,  the  main  support  of  patent  right,  and,  as 
the  case  quoted  shows,  it  has  been  used  in  modern  times  with 
effects  even  more  disastrous  for  the  industry  of  this  country  than 
in  those  ancient  days,  when  it  aroused  the  hostility  of  Lord  Coke 
and  the  antagonism  of  a  reforming  Parliament. 

Enough  has  been  already  said  about  the  mischievous  effect 
of  this  particular  injunction  upon  the  dyeing  trade  of  Lancashire. 
But  the  facts  cover  a  very  much  larger  field  than  this  particular 
sulpho-acid  dye,  a  field  in  fact  much  larger  than  the  field  of 
dyestuffs,  a  field  which  is  larger  even  than  the  whole  chemical 
industry.  But  we  are  more  immediately  concerned  with  its 
bearing  upon  the  proposal  to  establish  dye  manufacture  upon  a 
very  extensive  scale  within  this  country. 

From  that  point  of  view  the  important  fact  in  the  Levinstein 
case  is,  not  that  the  manufacture  of  a  particular  dye  was  pro- 
hibited within  the  realm,  but  that  the  way  of  improvement  was 
closed.  The  peculiar  mischief  of  this  decision  was  that  it  made 
it  more  advantageous  for  an  inventor  who  improved  upon  the 


PATENT  LAW   REFORM  393 

original  patent  to  go  to  Holland  and  practise  his  improved 
invention  as  a  secret  process  than  to  practise  it  in  this  country 
under  the  provisions  of  our  patent  law.  To  establish  such 
a  state  of  things  was  obviously  cutting  at  the  root  of 
development.  A  few  carefully  disposed  patents  can,  under  such 
a  system,  block  the  whole  development  of  an  industry  against  all 
the  world  except  only  those  privileged  people  who  chance  to  be 
the  holders  of  the  pioneer  patents.  It  is  a  matter  of  no  con- 
sideration that  these  pioneer  patents  themselves  may  be  perfectly 
worthless  for  all  practical  purposes.  It  is  their  existence,  not 
their  merit,  which  constitutes  the  strength  of  the  patentee's 
position. 

This  situation  was  clearly  apprehended  at  a  very  early  date  in 
the  history  of  the  chemical  industry  by  our  German  competitors. 
A  system  of  blocking  patents  has  been  an  organised  industry 
with  the  great  German  manufacturing  chemists  at  least  since  the 
year  1883  ;  and  when  we  hear  of  the  large  staffs  which  they  keep 
employed  upon  research  work  in  their  factories,  it  is  well  to 
remember  that,  over  and  above  those  results  of  this  laboratory 
industry  which  take  effect  in  improved  processes  and  products, 
there  is  a  large  output  of  novelties  which  are  improvements  only 
in  a  legal  sense  ;  the  real  value  of  which  is  that  they  eventuate 
in  patents  of  this  blocking  type  which  close  the  avenues  of 
improvement  to  other  inventors. 

It  is  impossible  from  any  available  data  to  ascertain  to  what 
extent  the  British  chemical  industry  has  been  sapped  by  means 
of  such  mischievous  patents,  but  this  system  of  sapping  has 
been  systematically  and  extensively  developed,  and  it  has  had  an 
immense  success. 

In  all  these  cases  the  cause  of  our  weakness  is  the  injunction. 
It  is  to  be  understood  that,  according  to  the  practice  which 
prevails  to-day,  a  perpetual  injunction  is  granted  as  a  matter  of 
course  to  protect  a  patentee  who  has  successfully  established  his 
patent  rights  against  an  infringer. 

Such  being  the  mischief,  we  may  now  turn  to  consider  what 
are  the  remedies  which  Parliament  has  provided.  The  earliest 
attempt  Was  embodied  in  a  section  (22)  of  the  Patent  Act  of 
1883,  which  provided  a  remedy  which  has  come  in  recent  years 
to  be  well  known  under  the  style  of  a  compulsory  licence. 

If  this  contrivance  of  a  compulsory  licence  had  been  effective, 
it  would  have  met  the  whole  difficulty.  It  would  have  prevented 


394         THE   BRITISH   COAL-TAR   INDUSTRY 

the  mischiefs  which  have  arisen,  and  would  probably  have  placed 
the  patent  law  of  this  realm  in  an  entirely  sound  position.  But 
a  very  hard  fate  has  pursued  the  reformers  of  our  patent  law. 
This  provision  was  still-born  and  never  produced  its  intended 
effect,  a  result  which  was  due  to  faults  of  draftsmanship. 
(A  detailed  discussion  of  the  Patent  Act  0/1883  follows  here?) 
The  provisions  of  the  Act  of  1883  concerning  compulsory 
licences  were  never  tested  experimentally,  for,  although  several 
petitions  were  lodged  and  carried  through  to  a  conclusion,  they 
were  all  carried  through  under  such  unfavourable  conditions  that 
anything  more  than  an  unsatisfactory  success  was  rendered  im- 
possible. It  is  not  surprising,  therefore,  that  the  agitation 
already  referred  to  for  a  reform  of  the  Act  of  1883  should  have 
gathered  head  and  eventually  should  have  prevailed  in  Parlia- 
ment. In  1900  a  Departmental  Committee  was  appointed  to 
consider  further  remedial  legislation,  and  in  particular  to  advise 
Parliament  as  to  the  adoption  of  the  Continental  provision  of 
the  compulsory  working  within  the  realm  of  patented  inventions. 
The  Committee  reported  against  the  compulsory  working  pro- 
vision, and  in  favour  of  a  reference  of  petitions  for  compulsory 
licences  to  the  High  Court.  The  report  contained  also  some 
other  suggestions,  and  in  the  ensuing  year  Parliament  proceeded 
to  legislate  on  lines  generally  indicated  by  the  Committee.  In- 
stead, however,  of  adopting  the  suggestion  that  petitions  for 
compulsory  licences  should  go  to  the  High  Court,  Parliament 
took  the  extraordinary  course  of  sending  them  for  consideration 
to  the  Privy  Council.  This  expedient  did  not  help  matters  at  all. 
The  division  of  authority  was  still  as  marked  and  as  mischievous 
as  when  the  petition  was  sent  to  a  referee,  and  the  practice  of 
the  Privy  Council  tended  rather  to  aggravate  than  to  reduce  the 
costs  incidental  to  the  carrying  of  the  petition  through.  So  far 
the  last  case  was  distinctly  worse  than  the  first,  and  in  1907 
Parliament  proceeded  to  deal  with  the  matter  for  a  third  time. 

The  Act  of  1907  was  closely  modelled  upon  the  German 
patent  law.  Accordingly  a  new  remedy  was  introduced  in  the 
shape  of  a  condition  making  the  working  of  a  patented  invention 
within  the  realm  compulsory,  but  the  nature  and  measure  of  the 
working  to  be  required  and  the  conditions  which  furnished  an 
excuse  or  imposed  liability  upon  a  patentee  were  left  to  be  settled 
by  the  judges  in  the  administration  of  the  law.  It  was  probably 
a  wise  expedient  on  the  part  of  Parliament  to  leave  these  matters 


PATENT   LAW  REFORM  395 

thus  in  a  plastic  condition  to  be  moulded  and  fixed  by  the  action 
of  the  judicature.  The  idea  no  doubt  was  that  the  obligation  of 
compulsory  working  would,  on  the  one  hand,  discourage  the 
practice  of  taking  patents  for  the  purpose  of  blocking  an  industry, 
and,  on  the  other  hand,  would  secure  the  development  within  the 
realm  of  industries  which  are  protected  by  patent  right.  The 
Act  has  only  been  in  operation  for  a  period  of  about  seven  years, 
and  it  is  too  soon  perhaps  to  attempt  anything  like  an  estimate 
upon  historical  foundations  of  its  possible  outcome.  It  may  be 
pointed  out,  however,  that  it  has  not  had  very  much  effect  so  far 
upon  the  chemical  industry.  To  those  who  have  a  practical 
acquaintance  with  the  conditions  of  the  problem  this  will  not  be 
surprising.  The  complications  which  it  presents  in  its  judicial 
aspects  are  enormous.  In  part  they  may  be  illustrated  by  the 
facts  of  the  Levinstein  case  which  have  been  described.  In  such 
a  case  as  that,  for  instance,  where  there  was  no  market  for  the 
goods  which  the  patentee  could  manufacture  and  a  large  market 
for  the  infringing  goods  which  he  did  not  know  how  to  make, 
what  is  the  patentee's  obligation  under  the  law  of  compulsory 
working  ?  Must  he  manufacture,  to  satisfy  the  law,  a  certain 
quantity  of  unmerchantable  goods,  or  is  he  to  be  held  liable 
to  manufacture  the  improved  goods  whose  production  is  the 
infringer's  secret  ?  The  inherent  difficulties  are  such  that  nothing 
would  be  less  surprising  than  that  it  should  be  found  in  the  end 
to  be  what  it  appears  to  have  been  in  the  beginning,  an  expedient 
wholly  ineffective  for  any  useful  purpose. 

Such  being  the  situation  which  has  actually  arisen,  it  will  be 
useful  to  consider  the  bearing  of  this  situation  upon  the  proposal 
now  made  to  establish,  in  competition  with  the  German  industry, 
a  self-sufficient  industry  in  this  country  in  the  manufacture  of 
dyestuffs.  We  may  take  it  for  granted  on  this  occasion  that 
no  insuperable  difficulty  will  arise.  So  far  as  research  and 
technical  education  are  concerned  there  is  not  likely  to  be  the 
smallest  difficulty  about  securing,  and  at  once  securing,  the 
necessary  trained  skill. 

Let  us  assume  that  the  works  are  started  and  in  successful 
operation.  That  fact  will  not  make  any  difference  to  the  subsist- 
ing patent  rights  in  this  country  of  which,  as  is  well  known, 
a  very  large  proportion  are  held  by  foreigners  and  others  whose 
interest  it  is  to  favour  the  foreign  competition  with  this  domestic 
industry.  Now  it  is  clear,  therefore,  that  there  will  be  a  strong 


396         THE   BRITISH   COAL-TAR   INDUSTRY 

disposition  to  repeat  the  Badische  coup  of  1883,  and  then,  adopt- 
ing the  language  of  the  judgment  in  that  case,  we  may  say  that 
notwithstanding  "  the  great  knowledge,  great  skill,  and  great 
perseverance "  which  will  be  brought  to  bear  in  building  up 
these  industries,  the  law  will  be  invoked  to  say  that  the  processes 
so  developed  cannot  be  used  in  the  production  of  the  colouring 
matters  manufactured  because  the  production  of  those  colouring 
matters  is  protected  by  patent  rights.  It  may  at  once  be  admitted 
that  the  new  institution  will  be  placed  in  a  very  different  position 
from  that  which  was  occupied  by  the  defendant  in  the  Badische 
and  Levinstein  action.  In  the  present  case  there  is  a  possibility 
of  applying  to  the  Board  of  Trade  for  a  compulsory  licence,  and 
if  it  were  certain  that  such  a  proceeding  would  succeed  it  would 
in  substance  remove  the  difficulty.  There  would  still  be  an 
important  question  of  procedure  to  be  considered,  but  that  is 
probably  not  of  great  importance.  It  cannot,  however,  be  taken 
for  granted  that  an  application  for  a  compulsory  licence  would 
succeed.  The  grounds  on  which  such  an  application  can  be  made 
are  strictly  limited  and,  in  fact,  very  narrow.  If  the  patentee 
himself  takes  adequate  steps  to  supply  the  British  market  with 
his  patented  goods,  then,  according  to  the  interpretation  adopted 
by  the  courts  of  this  provision  of  the  statute,  no  order  for  a 
compulsory  licence  can  be  made.  Now,  in  the  case  at  least  of 
important  goods  for  which  a  large  and  profitable  market  exists, 
there  seems  to  be  no  conceivable  reason  why  the  foreign  patentee 
himself  should  not  supply  the  demand.  It  is  quite  true  that 
he  may  be  called  upon  to  conduct  his  manufacture  within  the 
realm,  but  he  cannot  be  called  upon,  as  matters  stand,  to  grant 
a  licence  to  the  new  institution.  He  may  prefer  to  remain  an 
active  and  privileged  competitor  with  the  new  institution,  and 
so,  although  with  diminished  power  of  mischief,  may  still  succeed 
in  casting  his  blight  upon  the  undertaking.  The  carrying  on  of 
the  new  industry  under  these  conditions  would  seem  likely  to  be 
extremely  fruitful  of  litigation,  but  by  no  means  equally  assured 
of  success  ;  for  if  it  were  possible  to  close  any  particular 
manufacture  down  as  the  result  of  a  successful  patent  action, 
then  it  cannot  be  denied  that  nobody  at  the  present  moment 
is  in  a  position  to  say  what  precise  field  of  industry  will  in  the 
end  remain  open  to  the  proposed  institution.  This  is  the 
difficulty  with  which  the  promoters  are  faced.  The  research 
work  of  the  laboratories  of  which  we  have  lately  heard  so  much 


PATENT   LAW   REFORM  397 

has  resulted  in  an  immense  and  extremely  intricate  network  of 
patents  designed  to  protect,  by  their  entanglement,  the  whole 
field  of  chemical  industry,  which  the  Germans  have  made  their 
own.  Hitherto  these  entrenched  patents  have  afforded  very 
efficient  protection — partly,  no  doubt,  because  the  defence  of  the 
British  industry  has  been  left  to  the  uncoordinated  efforts  of 
British  manufacturers,  who  have  been  attacked  one  at  a  time  and 
beaten  in  detail.  It  does  not,  of  course,  follow  that  it  would  be 
equally  successful  against  a  fully  organised  effort  to  create  a 
British  industry  ;  but,  on  the  other  hand,  nobody  can  be  justified 
in  asserting,  as  our  patent  law  is  understood  and  administered  at 
the  present  time,  that  such  a  large  and  organised  institution 
would  have  any  better  chance  than  the  resolute  manufacturer,  like 
the  Levinstein  Company  in  1883,  of  making  an  effective  stand 
against  the  overwhelming  brute  force  of  a  judicial  injunction. 

(An  analysis  of  defects  in  the  existing  patent  law,  and  suggestions 
for  their  removal,  follow  here.} 

Patent  right  is  a  privilege  of  such  a  character  that  it  would 
not  be  impaired  for  the  purposes  of  beneficent  operation  by  being 
subject  to  a  larger  discretion  in  the  exercise  of  the  power  of 
suspension  reserved  to  the  Crown  than  is  provided  for  in  the 
Patent  Act.  The  objects  of  the  grant  are  threefold  : — 

1.  The  common  good  and  benefit  to  the  realm. 

2.  Reward   and  recompense   for  the  industry,  trouble,  and 
charges  of  the  patentee. 

3.  The  encouragement  of  other  inventors  in  such  laudable 
and   commendable   labours   as   may  tend  to  the  good  use  and 
service  of  the  realm. 

Now  it  is  obvious,  and  may  be  taken  to  be  generally  admitted, 
that  such  an  absolutely  unrestricted  power  of  exclusive  manu- 
facture as  was  conceded  in  the  Badische  and  Levinstein  case 
tends  directly,  not  to  promote,  but  to  subvert  the  first  of  these 
objects.  It  tends  also  to  produce  that  just  cause  of  grievance 
which  it  was  one  of  the  declared  objects  of  the  Crown  to  avoid 
in  connection  with  the  grant.  Hence  it  may  be  said,  with 
confidence,  that  the  relief  by  injunction  which  was  granted  in 
the  Levinstein  case  is  subversive  of  the  objects  of  the  patent 
grant  itself.  The  practical  question,  therefore,  is  not  whether 
the  power  to  restrain  infringement  by  injunction  shall  be  wholly 
uncontrolled,  but  to  what  extent  it  should  be  controlled.  The 
obvious  answer  to  this  question  is  that  it  ought  to  be  controlled 


398         THE   BRITISH    COAL-TAR   INDUSTRY 

to  such  an  extent  as  to  secure  all  the  objects  of  the  grant ;  includ- 
ing the  avoidance  of  any  just  cause  of  grievance.  An  answer 
in  those  terms,  however,  is  not  very  instructive,  because  the 
practical  difficulty  is  to  discover  those  rules  of  practice  which  will 
attain  the  end.  One  inference  may,  however,  with  confidence 
be  drawn  even  from  this  extremely  indefinite  statement  of  the 
principle,  and  it  is  this  :  The  injunction  ought  not  to  go  as 
mere  matter  of  course,  and  without  consideration  of  the  cir- 
cumstances of  the  case.  A  court,  when  granting  an  injunction, 
ought  to  satisfy  itself  that  the  injunction  will  not  cause  the 
inconveniences  which  followed  in  the  Badische  case,  and,  therefore, 
something  more  than  mere  infringement  ought  to  be  established 
to  justify  a  court  in  granting  a  perpetual  injunction. 

The  general  principle  with  regard  to  injunctions  was  thus 
stated  by  Lord  Brougham  : — 

"  The  principle  which,  as  I  humbly  conceive,  ought,  generally 
speaking,  to  be  the  guide  of  the  court  and  to  limit  its  discretion 
in  granting  injunctions,  at  least  where  no  very  special  circum- 
stances occur,  is  that  only  such  restraint  shall  be  imposed  as 
may  suffice  to  stop  the  mischief  complained  of." — Blackmore  v. 
The  Glamorganshire  Canal  Navigation,  i  Mylne  and  Keen,  185. 

Coming  to  a  narrower  and,  for  our  present  purpose,  more 
pointed  statement  of  the  principle,  we  have  it  formulated  by 
Lord  Lindley  in  the  following  terms  : — 

"  The  very  first  principle  of  injunction  law  is  that  prima  facie 
you  do  not  obtain  injunctions  to  restrain  actionable  wrongs  for 
which  damages  are  the  proper  remedy." — London  and  Blackwall 
Ry.  v.  Cross,  Law  Rep.,  31  Chanc.  Div.,  p.  369. 

The  careful  observation  of  this  salutary  rule  would  obviously 
preclude  such  mischievous  results  as  we  are  now  discussing, 
and  with  such  authority  as  it  is  possible  to  cite  for  the  rule 
one  may  without  presumption  speak  of  the  existing  and 
mischievous  practice  as  being  a  lapse  from  the  sound  doctrine 
of  the  English  law. 

Let  it  be  supposed,  then,  that  by  some  means,  either  by 
a  voluntary  recurrence  on  the  part  of  the  courts  to  Lord 
Brougham's  rule,  or,  failing  that,  by  legislation,  we  were  to 
arrive  at  a  satisfactory  settlement  of  this  practice,  is  there  any 
reason  to  think  that  the  system  would  work  badly  and  would 
unfairly  prejudice  the  rights  of  a  patentee  ?  For  the  purpose 
of  discussing  this  question,  I  will  assume  that  recourse  is  had 


PATENT   LAW    REFORM  399 

to  Parliament,  and  that  an  enactment  has  been  put  upon  the 
statute  book  which  goes  in  one  particular  beyond  the  older 
practice  of  the  Court  of  Chancery.  I  will  assume,  that  is  to  say, 
that  the  enactment  provides  in  effect  : — 

(1)  That  no  perpetual  injunction  shall  in  any  case  be  granted 
to  restrain  infringement  of  a  patent  right,  but  only  an  injunction 
to  stand  until  further  order  ; 

(2)  That  no  injunction  shall  be  granted  to  restrain  infringe- 
ment of  a  patent  right  unless  it  is  proved  to  the  satisfaction  of 
the  court  that  the  mischievous  result  to  the  patentee  from  the 
infringement    proved    is    such   that  he  cannot  obtain    adequate 
relief  in  respect  thereof  from   the  defendant  charged  with  the 
infringement. 

What  would  be  the  result  upon  patent  rights  of  such  a 
modification  of  the  existing  practice  of  the  courts  ? 

(1)  It  would  at  once  put  an  end  to  the  blackmailing  type 
of  patent  action.     In  recent  years  a  practice  has  grown  up  of 
bringing  patent  actions  against  perfectly  innocent  infringers  who 
have  no  sufficient  interest  in  the  dispute  to  make  an  effective 
defence.     Now  it  is  clear  that  if  no  injunction  could  be  granted, 
but  only  damages  in  a  case  of  that  sort,  the  patentee  would  find 
that  type  of  action  a  very  unprofitable  investment. 

(2)  Again,  in  a  case  such  as  the  Badische  action,  it  is  clear 
that  the  patentees  would  have  been  wholly  unable  to  destroy 
the  British  industry  which  they  set    themselves  to  attack.     In 
fact,  it  is  probable  that  the  result  of  that   action  would  in  such 
a   case    have  been  more  satisfactory  to  them  as  well  as  to  the 
defendant  company  than  in  fact  it  was.     If  they  could  not  have 
obtained  an  injunction  they  would  have  had  to  be  content  with 
damages  ;  and  although  it  may  be  presumed  that  in  the  circum- 
stances of   that  case  the  damages  would  have  been  small,  they 
still  would  have  amounted  to  something. 

The  proposal  to  establish  a  large  manufacturing  industry 
under  the  existing  conditions  of  the  aniline-dye  manufacture 
is  one  which  raises  not  only  the  commercial  questions  of 
capitalisation  and  organisation,  but  also,  in  a  very  pressing  form, 
the  comparatively  dormant  question  of  a  reform  of  the  patent 
law.  The  comparative  backwardness  of  our  manufacture  in 
this  line,  easily  as  it  is  explained  by  those  who  allege  the 
indolence,  supineness,  and  inaptitude  for  this  class  of  industry 
of  the  British  manufacturer,  can  nevertheless  be  fully  explained 


400         THE   BRITISH   COAL-TAR   INDUSTRY 

only  when  the  pitfalls  of  our  patent  law  are  also  taken  into 
account.  There  is  no  doubt  that  both  in  1852  and  in  1883 
substantial  improvements  were  introduced  into  the  administra- 
tion of  our  patent  law.  That  the  Act  of  1907  made  for 
improvement  is  open  to  much  question.  It  complicated  our 
system  by  the  introduction  of  incongruous  elements,  chiefly 
from  the  German  patent  code,  but  it  left  untouched  the  mischiefs 
which  destroyed  the  British  manufacture  of  aniline  dyes,  and  laid 
us  open  to  misunderstanding  and  reprisal  in  foreign  countries 
without  securing  any  countervailing  advantage  for  our  own 
manufactures  and  manufacturers. 


XXXI. :    1915 

THE    SUPPLY  OF  DYEWARES 

BY  PROFESSOR  R.  MELDOLA,  D.Sc.,  LL.D.,  F.R.S. 

(Abstract  of  Presidential  Address  to  the  Institute  of  Chemistry, 
ist  March  1915) 

EARLY  in  August  last  year,  as  appeared  from  a  question  raised 
in  the  House  of  Commons,  it  was  foreseen  that  difficulties  might 
arise  in  this  country,  and  that  certain  industries — especially  those 
connected  with  textiles — might  be  seriously  affected  through  the 
stoppage  of  supplies  of  chemical  products,  more  particularly 
dyestuffs,  for  which  we  were  dependent  to  a  preponderating 
extent  upon  German  factories. 

I  may  be  pardoned  on  the  present  occasion  if  I  venture  to 
recall  a  warning  which  I  sounded  nearly  thirty  years  ago.  As 
far  back  as  1886,  I  foresaw  that  the  coal-tar  colour  industry  as 
conducted  by  us  was  doomed  to  decadence  in  this  country.1 
Systematic  inquiries  made  among  the  consumers  revealed  the 
fact  that  even  at  that  time  90  per  cent,  of  the  dyestuffs  then  in 
use  here  were  of  foreign  manufacture.  The  voluminous  news- 
paper correspondence  which  has  been  going  on  in  connection 
with  this  subject  all  over  the  country  during  the  last  few  months 
shows  that,  in  military  parlance,  no  lost  ground  has  been  regained — 
before  the  outbreak  of  the  war  we  were  still  importing  nine-tenths 
of  our  colouring  matters  from  Germany  and  Switzerland.  Since 
1886,  on  every  suitable  occasion,  I  have  been  endeavouring 
to  instil  into  the  public  mind  the  lesson  that  the  development 
of  this  industry  abroad  has  been  due  to  the  recognition  and 
utilisation  by  manufacturers  of  the  results  of  chemical  research. 
To  me,  therefore,  the  crisis  threatening  our  textile  industries  is 
no  matter  for  surprise — it  appears  simply  as  a  relationship  of 

1  See  Meldola,  Jour.  Soc.  Arts,  1886.     See  p.  121,  ante. 

401  26 


402         THE   BRITISH   COAL-TAR   INDUSTRY 

effect  to  cause.  It  is  generally  supposed  that  the  prophet  who, 
justified  by  events,  is  enabled  to  say  "  I  told  you  so,"  is  privileged 
to  regard  himself  with  the  greatest  complacency.  In  the  present 
case,  the  only  feeling  I  am  able  to  express  is  one  of  humiliation  : 
it  is  absolutely  painful  that  under  the  stress  of  circumstances 
our  weakness  should  have  been  laid  bare  to  all  the  nations — a 
weakness  for  which  there  can  be  found  no  justification  in  the 
plea  that  no  alarm  had  been  raised  or  that  the  supply  of  chemical 
talent  in  this  country  was  inadequate. 

The  President  of  the  Board  of  Trade  appointed  early  in 
August  a  committee  for  the  purpose  of  advising  the  Government 
with  respect  to  the  means  of  meeting  the  national  requirements, 
with  the  Lord  Chancellor,  Viscount  Haldane,  as  chairman.  From 
this  main  committee  there  was  subsequently  formed  a  sub-com- 
mittee for  dealing  especially  with  the  manufacture  of  dyestuffs, 
under  the  chairmanship  of  Lord  Moulton,  whose  extensive 
experience  in  matters  connected  with  this  branch  of  applied 
chemistry  is  well  known. 

It  is  now  public  knowledge  that  a  scheme  formulated  by 
the  Government  in  consultation  with  a  committee  representa- 
tive of  the  great  dye-using  organisations  was  put  forward  at  the 
close  of  last  year,  and  after  full  discussion  by  those  immediately 
concerned  was  finally  referred  back  for  modification.  This  is 
not  the  occasion  for  entering  into  a  detailed  analysis  of  the 
various  grounds  on  which  the  scheme  was  considered  unsatis- 
factory, but  the  Government  has  determined — as  I  think,  wisely 
— not  to  allow  the  project  to  fall  through,  and  has  now  launched 
a  new  scheme  which  differs  from  the  first  in  certain  important 
particulars.  Whether  this  new  scheme  will  materialise  remains 
to  be  seen  :  so  far,  all  that  can  be  said  is  that  a  considerable 
number  of  the  dye-consuming  companies  appear  to  be  favourably 
disposed  towards  it.  It  would  be  out  of  place  here  to  attempt 
to  explain  or  to  criticise  the  scheme  as  it  stands,  but  I  want  it 
to  be  clearly  understood,  as  there  has  been  much  public  mis- 
apprehension on  this  point,  that  for  neither  of  these  schemes  is 
the  Board  of  Trade  Advisory  Committee  or  the  Dyestuffs  Sub- 
Committee  in  any  way  responsible.  The  grounds  on  which  it 
was  considered  that  public  action  was  imperatively  called  for 
were  set  forth  most  clearly  in  an  address  delivered  by  Lord 
Moulton  at  Manchester,  on  8th  December  of  last  year,1  and  in 

1  See  p.  351,  ante. 


THE   SUPPLY   OF   DYEWARES  403 

that  address  he  stated  explicitly  that  he  only  held  himself  re- 
sponsible for  the  advice  that  the  Government  should  take  action, 
but  not  for  the  particular  shape  or  form  which  that  action  should 
assume.  Out  of  the  present  situation,  therefore,  there  arise 
certain  general  considerations  which  the  chemical  profession  will 
do  well  to  take  note  of,  and  for  this  reason  I  will  venture  to 
direct  your  attention  to  some  of  them. 

In  the  first  place,  stating  the  case  baldly,  and  in  the  broadest 
possible  terms,  the  principle  is  adopted  that  there  should  be 
established  a  company  in  which  the  consumers  should  be  the 
chief  shareholders,  and  which  the  Government  should  subsidise 
by  advancing  capital  at  a  certain  rate  of  interest  to  the  extent 
of  £ i, 000,000.  It  is  unnecessary  to  go  into  details,  but  it  will 
be  seen  that  the  scheme  is  in  a  way  a  co-operative  one  and  that, 
for  the  first  time,  we  have  a  distinct  proposal  in  this  country  for 
the  establishment  of  a  State-aided  industry.  It  is  beyond  our 
province  to  discuss  this  proposal  in  its  economic  or  political 
bearings.  In  view  of  the  great  interests  at  stake,  the  policy 
appears  to  me  to  be  a  sound  one,  as  was  admitted  by  both 
political  parties  when  the  proposal  was  mentioned  in  the  House 
of  Commons  last  November  by  the  President  of  the  Board  of 
Trade  (Times  report,  28th  November  1914).  What  concerns 
us  most  as  representatives  of  the  chemical  profession  is  that  our 
aspect  of  this  great  industry  should  be  kept  well  to  the  fore  in 
the  present  scheme,  or  in  any  other  scheme  that  may  hereafter 
be  put  forward. 

In  the  next  place,  I  take  it  for  granted  that  we  all  desire  to 
see  the  restoration  of  the  coal-tar  colour  industry  to  this  country, 
and,  be  it  noted,  not  only  restored,  but  permanently  retained 
after  the  war.  Now,  the  discussions  of  the  Government  schemes 
in  various  parts  of  the  country  by  dye-consuming  organisations, 
Chambers  of  Commerce,  and  so  forth,  have  all  centred  round 
political  or  economic  questions  ;  that  which  is  to  us  the  vital 
principle,  viz.  adequate  chemical  control,  has  been  subordinated 
or  left  out  of  consideration  altogether.  It  is  the  old,  old  story 
— we  wrangle  over  the  question  as  to  the  method  by  which  the 
industry  shall  be  established  and  maintained  here,  whether  by 
Free  Trade  or  Protection,  or  Subvention  or  by  any  other  device, 
and  we  leave  out  of  consideration  the  question  whether  a  few 
years  hence  there  will  be  anything  in  the  way  of  dyestuffs  worth 
protecting  ;  whether  there  will  be  a  sufficient  basis  of  material 


404         THE   BRITISH   COAL-TAR   INDUSTRY 

products  left  for  the  politicians  and  economists  and  business 
people  to  wrangle  over.  It  is  not  a  purely  business  problem 
which  the  Government  has  undertaken  to  solve  ;  it  is  primarily 
a  chemical  problem.  It  is  not  even  a  business  problem  in  the 
ordinary  trade  sense,  because  the  main  object  is  at  first  to  supply 
our  own  wants,  and  the  chief  consumers  are  to  be  the  chief  pro- 
ducers. The  question  of  business  in  the  sense  of  export  trade 
is  at  present  remote. 

The  conditions  which  have  to  be  met  if  we  wish  to  see  this 
country  once  more  the  home  of  the  colour  industry  may  be 
well  known  to  us  here,  but  are  certainly  imperfectly  understood 
by  the  public.  Even  those  most  concerned — those  who  are 
invited  to  subscribe  the  capital — appear  in  most  cases  to  have 
an  idea  that  all  that  is  necessary  is  to  find  the  money,  secure 
the  Government  aid,  appoint  a  board  of  business  directors,  and 
lo  !  the  industry  will  forthwith  spring  into  existence  ready  to 
cope  with  all  emergencies.  Now,  what  are  the  facts  of  the 
case  ?  About  five  hundred  different  dyestuffs  of  definite  com- 
positions have  been  given  to  tinctorial  industry  as  the  products 
of  chemical  research.  Of  these,  a  certain  number  only  can  be  and 
are  being  made  in  this  country,  the  total  output  of  our  factories 
being  at  present  inadequate  for  the  requirements  of  our  textile 
industries.  The  first  step  to  be  taken,  therefore,  is  to  enlarge 
and  develop  our  existing  factories  so  that  the  dyes  which  can 
be  made  here  should  be  turned  out  in  larger  quantities.  This 
necessity  has,  of  course,  been  provided  for  in  the  Government 
scheme,  and  so  far  so  good.  Moreover,  if  the  extension  of 
the  existing  factories  still  leaves  us  with  insufficient  supplies, 
new  factories  must  be  erected  and  equipped.  That  also  is  pro- 
vided for  in  the  scheme ;  but  if  we  want  to  establish  the 
industry  here  permanently  we  must  look  beyond  all  this — where 
shall  we  be  left  after  the  war  ?  We  shall  be  in  possession  of 
processes  for  making  a  certain  number  of  dyes,  and  the  supply 
of  this  particular  set  of  products  may  possibly  be  sufficient  for 
the  particular  purposes  for  which  they  are  required.  Let  us 
label  these  provisionally  "  staple  products."  But  there  will  still 
be  an  outstanding  number — probably  a  majority — of  other  pro- 
ducts which  we  have  never  yet  made  here,  and  for  the  working 
out  of  these  processes  no  combination  of  "  business  "  talent  is 
of  the  slightest  value.  I  repeat,  it  is  not  a  business  question, 
but  a  chemical  question,  and  it  is  by  chemkal  research  alone  that 


THE   SUPPLY   OF   DYEWARES  405 

our  colour  industry  can  be  saved  in  the  long  run.  Consider  the 
leeway  that  we  have  to  make  up.  The  German  colour  industry 
has  been  built  up  by  the  utilisation  of  the  results  of  research 
carried  on  in  the  factories  and  universities  and  technical  schools 
for  a  period  of  over  forty  years  !  To  suppose  that  we  can 
retrieve  our  position  after  forty  years  of  neglect  by  starting  a 
company  the  directorate  of  which  is  to  consist  solely  of  business 
people  is  simply  ludicrous.  It  was  against  this  principle  that  I 
ventured  to  raise  my  voice  in  the  Times  of  2Oth  January  last,  and 
I  am  extremely  glad  to  find  that  not  only  the  chemical  and 
technical  worlds,  but  the  large  and  representative  body  of  dye 
users  and  producers  which  form  the  Dyewares  Supply  Enquiry 
Committee  of  the  Society  of  Dyers  and  Colourists,  fully  endorse 
this  view  and  have  forwarded  to  the  Board  of  Trade  a  resolution, 
passed  at  Manchester  last  month,  in  support  thereof.  A  meeting 
of  the  Federation  of  the  Light  Leather  Trades  held  at  the 
Leathersellers'  Hall  on  22nd  February  passed  a  similar  resolution. 
It  is  satisfactory  to  learn  that  there  are  at  any  rate  some  of  the 
dye-consuming  organisations  which  have  grasped  the  situation 
scientifically.  To  imagine  that  a  dyer,  however  skilful  he  may 
be,  is,  by  virtue  of  his  occupation,  necessarily  competent  to 
direct  the  affairs  of  a  company  which  is  concerned  with  the 
manufacture  of  the  dyes  which  he  uses,  is  about  as  sensible  as 
the  assumption  that  a  person  who  can  tell  the  time  by  his  watch 
is  thereby  qualified  to  undertake  the  direction  of  a  factory  for 
the  construction  of  chronometers. 

One  feature  of  the  new  scheme  which  the  chemical  profession 
will  view  with  favour  is  the  distinct  recognition  of  research  as  a 
necessity  for  the  development  of  the  industry.  The  Government 
"will,  for  ten  years,  grant  not  more  than  £100,000  for  ex- 
perimental and  laboratory  work."  That,  although  an  inadequate 
endowment,  is  certainly  a  concession  which  marks  an  advance  in 
official  opinion  for  which  we  are  grateful.  It  will  be  for  the 
satirist  of  the  future  to  point  out  that  it  required  a  European 
war  of  unparalleled  magnitude  to  bring  about  this  official  recog- 
nition of  the  bearing  of  science  upon  industry.  It  would  be 
but  a  truism  to  state  here  the  purposes  for  which  research  is 
required  ;  the  question  we  have  to  raise  is — Who  is  to  direct 
this  research  ?  A  directorate  of  purely  business  people  would 
certainly  be  incompetent  ;  a  board  composed  of  dye  users  could 
do  no  more  than  indicate  what  dyestuffs  were  needed.  True,  it 


406         THE   BRITISH   COAL-TAR   INDUSTRY 

is  proposed  that  the  company  should  take  powers  to  secure  the 
assistance  of  a  committee  of  experts,  but  this  appears  to  me  to 
be  simply  a  reversion  to  that  policy  of  "  drift "  which  I  have 
for  so  long  been  struggling  to  overthrow.  The  experts  are,  as 
usual  in  this  country,  subordinated  ;  their  assistance  is  to  be 
invoked  at  the  discretion  of  a  board  the  members  of  which  can 
have  no  real  knowledge  of  the  conditions  necessary  for  producing 
the  materials  they  require  now — still  less  would  they  be  com- 
petent to  point  out  dangers  ahead.  The  "staple  products" 
upon  which  they  are  asked  to  stake  their  capital  may  a  few  years 
hence  be  superseded  by  the  products  of  subsequent  discovery. 
The  policy  of  attempting  to  run  a  highly  specialised  and  rapidly 
developing  branch  of  organic  chemical  industry  by  a  company 
of  business  people,  with  expert  assistance  when  required,  is  fatal 
if  we  want  to  establish  the  industry  permanently  here.  The 
group  of  industries  which  have  arisen  from  the  products  of  the 
tar-still  are  not  going  to  remain  stagnant  after  the  war,  and  it 
is  scientific  guidance  and  not  mere  assistance  that  will  keep  them 
alive.  It  is  the  expert,  and  the  expert  only,  who  can  foresee 
the  course  of  development,  who  can  keep  in  touch  with  the 
progress  of  research,  and  who  can  direct  with  intelligence  the 
campaign  against  our  competitors.  If  such  scientific  direction  is 
withheld,  all  schemes  are  sooner  or  later  bound  to  end  in  failure. 


XXXII.:    1915 

THE    POSITION    OF   THE   ORGANIC 
CHEMICAL   INDUSTRY 

BY  PROFESSOR  W.  H.  PERKIN,  F.R.S. 

(Presidential  Address  delivered  to  the  Chemical  Society,  25th  March  1915  : 
Journal  of  the  Chemical  Society,  1915,  p.  557) 

THE  subject  which  1  have  chosen  for  my  address  on  this  occasion 
must  always  be  regarded  as  of  the  highest  importance,  not  only 
to  this  Society,  but  also  to  the  country  at  large,  because  of  its 
intimate  connection  with  the  prosperity  of  so  many  of  our  largest 
and  most  successful  industries.  It  is  a  subject  which  has  been 
discussed  over  and  over  again  at  scientific  societies,  in  scientific 
journals,  and  particularly  in  the  newspapers  by  chemists,  manu- 
facturers, politicians,  and  the  general  public.  In  his  valuable 
presidential  address  to  this  Society  in  1907,  entitled  "The 
Position  and  Prospects  of  Chemical  Research  in  Great  Britain," 
Professor  Meldola  had  much  to  say  about  the  bearing  of  research 
on  the  position  of  industry  ;  and  in  1909  the  same  writer  dis- 
cussed very  fully  the  question  of  the  value  of  education  and 
research  in  connection  with  applied  chemistry  in  his  presidential 
address  to  the  Society  of  Chemical  Industry.  It  would  therefore 
seem  scarcely  necessary  that  I  should  take  up  your  time  by 
bringing  these  matters  to  your  notice  again.  I  do  not  propose, 
however,  to  apologise,  partly  because  I  am  of  the  opinion  that  a 
summary  of  the  position  of  the  organic  chemical  industry  in  as 
few  words  as  possible  will  not  be  out  of  place  and  may  be  useful, 
but  more  particularly  because,  in  spite  of  the  large  amount  of 
literature  bearing  on  the  subject,  I  feel  convinced  that  the  causes 
of  the  decadence  of  this  industry  in  this  country  are  still  imper- 
fectly understood. 

407 


4o8         THE   BRITISH    COAL-TAR   INDUSTRY 

The  seriousness  of  the  position  is  readily  grasped  when  it  is 
borne  in  mind  that  the  value  of  the  colouring  matters  consumed 
in  this  country  is  at  least  £2,000,000  per  annum,  and  that  more 
than  90  per  cent,  of  this  quantity  comes  from  Germany  ;  and, 
when  it  is  remembered  that  these  dyes  are  essential  to  textile 
industries  representing  at  least  £200,000,000  per  annum,  and 
employing  more  than  1,500,000  workers,  it  is  easy  to  see  to 
what  an  alarming  extent  these  great  industries  are  in  the  grip 
and  power  of  the  Germans.  There  are,  of  course,  many  other 
industries  which  depend  on  colouring  matters  for  their  existence, 
such  as,  for  example,  the  wallpaper,  the  printing,  and  paint 
industries,  to  all  of  which  lakes  and  pigments  are  absolutely 
essential,  and  of  late  years  almost  the  whole  of  these  have  been 
imported  from  Germany.  Again,  the  enormous  quantities  of 
organic  chemicals  required  for  photographic  purposes — such  as, 
for  example,  pyrogallic  acid,  hydroquinone,  metol,  and  many 
other  similar  developers, — the  natural  and  artificial  products 
employed  in  such  huge  quantities  in  the  manufacture  of  scents 
and  perfumes,  the  synthetical  and  other  drugs  which  have  in 
some  ways  revolutionised  medical  science,  and  also  many  of  the 
more  important  disinfectants,  have  been  almost  exclusively  made 
in  Germany.  We  may  add  to  this  list  the  vast  trade  in  fine 
chemicals,  for  here  we  are  again  completely  outclassed,  since 
there  are  no  firms  in  this  country  which  can  compete  with 
Kahlbaum,  Merck,  Schering,  de  Haen,  and  a  host  of  others 
either  in  the  range  or  the  purity  of  their  products,  and  it  has 
long  been  our  habit  to  import  almost  all  our  organic  fine 
chemicals  from  Germany.  It  may  indeed  be  said  that  Germany 
has  no  competitor  worth  considering  in  the  whole  domain  of 
organic  chemical  industry.  That  we  should  have  allowed  trades 
of  such  magnitude  to  pass  almost  completely  into  the  hands  of 
a  foreign  nation  seems  incredible,  and,  as  the  inevitable  result, 
we  are  face  to  face  with  the  serious  position  that,  the  foreign 
supply  having  stopped,  stocks  are  rapidly  vanishing  and  prices 
are  rising  to  such  an  impossible  level  that  the  progress  of  several 
of  our  industries  is  greatly  hampered.  Indigo,  perhaps  the 
most  essential  of  all  dyes,  is  manufactured  entirely  by  the  great 
German  colour  works,  and  the  stock  in  this  country  a  few  weeks 
ago  was  so  low  that  the  price  rose  to  at  least  ten  times  what  it 
was  before  the  war  ;  the  same  thing  is  happening  in  other  cases, 
and  many  dyes  cannot  be  obtained  at  any  price.  Obviously  we 


THE   ORGANIC   CHEMICAL   INDUSTRY      409 

must  take  warning,  and  not  allow,  in  the  future,  our  textile  and 
so  many  other  similar  industries  to  be  controlled  in  this  way 
by  the  foreigner,  and  to  be  in  danger  of  being  brought  to  a 
standstill. 

How  are  we  to  explain  the  fact  that  we  have  allowed  some 
of  our  most  important  industries  to  get  into  this  critical  condition, 
and  what  do  we  propose  to  do  to  remedy  this  state  of  things 
and  prevent  any  recurrence  in  the  future  ?  No  one  doubts  for 
a  moment  that  the  wonderful  opportunity  of  establishing  a  great 
national  industry,  due  to  the  discovery  of  the  aniline  dyes  in 
this  country,  has  been  allowed  to  escape  us,  and  various  reasons 
have  been  put  forward  to  explain  the  loss  of  the  colour  industry. 
There  can  be  no  doubt  that  a  good  many  different  causes  have 
been  at  work.  One  of  the  main  reasons  for  our  position  is  that 
we  as  a  nation,  and  our  manufacturers  in  particular,  have  failed 
to  understand  the  extreme  complexity  of  the  scientific  basis  of 
organic  chemical  industry,  and  have  concluded  that  this  industry 
could  be  carried  on  much  in  the  same  way  as  the  manufacture 
of  sulphuric  acid,  caustic  soda,  and  other  heavy  chemicals.  The 
manufacturer  has  always  been  unwilling  to  acknowledge  that 
neglect  of  science  in  his  works  is  the  real  cause  of  his  failure  to 
retain  the  colour  industry  in  this  country,  and  has  therefore  put 
forward  all  sorts  of  other  reasons  to  explain  his  want  of  success. 

Thus  it  has  been  urged  repeatedly  that  our  patent  laws  were 
greatly  to  blame,  and  that  these  laws  were  such  that  an  English 
patent  was  no  protection,  and  that  so  soon  as  anything  new  had 
been  discovered  in  this  country  the  Germans  at  once  set  to  work 
to  manufacture  it. 

Even  if  this  were  true — and  there  may  be  some  truth  in  it — 
it  does  not  explain  why  the  Germans  were  able  to  obtain  their 
raw  material  as  they  did  in  this  country,  to  transport  it  to  Ger- 
many, and  then  to  send  the  dye  over  here,  and  at  the  same  time 
to  make  a  handsome  profit  out  of  the  transaction.  Again,  it  has 
been  urged  that  the  obstacles  to  the  use  of  pure  alcohol  which 
existed  at  the  end  of  the  last  century  played  a  great  part  in 
bringing  about  the  decadence  of  the  coal-tar  colour  industry  in 
this  country.  Possibly  there  has  been  some  hardship  in  special 
cases,  but  a  Departmental  Committee  of  the  Board  of  Trade  took 
evidence  from  a  large  number  of  experts  in  this  country  and  in 
Germany,  and  issued  a  report  on  "  Industrial  Alcohol"  in  1905, 
and  the  Committee  arrived  at  the  conclusion  that,  as  a  statement 


4io         THE  BRITISH   COAL-TAR   INDUSTRY 

of  historical  fact,  the  assertion  that  the  coal-tar  industry  has  been 
lost  to  this  country  on  account  of  obstacles  to  the  use  of  pure 
alcohol  is  devoid  of  substantial  foundation.1  Of  late  years  the 
restrictions  on  the  use  of  duty-free  alcohol  have  been  so  relaxed 
and  the  denaturants  which  may  be  employed  are  of  such  a  wide 
range,  including  as  they  do  the  actual  articles  to  be  manufac- 
tured,2 that  there  is  probably  at  the  present  time  less  difficulty 
put  in  the  way  of  the  manufacturer  here  than  is  the  case  in 
Germany. 

It  is  quite  obvious  that  other  reasons  than  those  I  have  just 
mentioned  must  be  found  to  account  for  the  gradual  transference 
of  the  coal-tar  industry  to  Germany.  The  decadence  of  this 
industry  and  its  gradual  transference  to  Germany  may  be  said  to 
have  begun  during  the  period  1870-75.  It  was  in  1874  that 
the  works  of  Perkin  &  Sons  at  Greenford  Green  was  sold  to  the 
firm  of  Brooke,  Simpson  &  Spiller,  and  these  works  were  then 
in  the  most  prosperous  condition,  and  much  in  advance  of  any- 
thing that  existed  in  Germany. 

One  reason  for  the  sale  was  my  father's  natural  dislike  to  an 
industrial  career,  and  his  desire  to  devote  himself  entirely  to 
pure  chemistry.  There  was,  however,  a  much  more  weighty 
consideration  which  played  the  really  important  part  in  his 
decision  to  dispose  of  the  works. 

It  was  recognised — and,  as  the  subsequent  history  of  the  coal- 
tar  industry  has  shown,  correctly  recognised — that  the  works 
could  not  be  carried  on  successfully  in  competition  with  the  rising 
industry  in  Germany  unless  a  number  of  first-rate  chemists  could 
be  obtained  and  employed  in  developing  the  existing  processes, 
and  more  particularly  in  the  all-important  work  of  making  new 
discoveries.  I  remember  quite  well  that  inquiries  were  made  at 
many  of  the  British  universities  in  the  hope  of  discovering  young 
men  trained  in  the  methods  of  organic  chemistry,  but  in  vain. 
There  cannot  be  any  doubt  that  the  manufacturer  of  organic 
colouring  matters  during  the  critical  years  1870-80  was,  owing 
to  the  neglect  of  organic  chemistry  by  our  universities,  placed  in 
a  very  difficult  and  practically  impossible  position.  At  that  time 
organic  chemistry  was  not  recognised  by  the  older  universities, 

1  See  p.  228,  ante. 

2  For  example,  the  manufacturer  of  pure  ether  may  denature  the  alcohol 
he  uses  by  the  addition  of  a  little  sulphuric  acid,  and,  in  the  case  of  diethyl- 
aniline,  this  substance  or  aniline  may  be  used  as  the  denaturant,  and  so  on. 


THE   ORGANIC   CHEMICAL   INDUSTRY      411 

and  the  newer  universities,  which  have  since  done  so  much  for 
the  progress  of  science,  had  not  come  into  existence.  It  is  surely 
remarkable  that  the  study  of  so  important  a  subject  as  organic 
chemistry  should  not  only  have  been  practically  ignored  by  our 
universities  in  the  past,  but  that  even  at  the  present  day  it  does 
not  flourish  in  the  way  it  does  in  almost  every  university  and 
technical  school  in  Germany. 

This  seems  to  me  the  more  remarkable  when  it  is  borne  in 
mind  that  all  problems  connected  with  life,  either  in  the  animal 
or  vegetable  kingdom,  are  essentially  problems  which  depend  on, 
and  are  largely  controlled  by,  organic  chemistry,  and  it  is  there- 
fore clear  that  little  progress  can  be  made  towards  the  solution  of 
such  problems  until  the  processes  of  organic  chemistry  are  clearly 
understood.  Quite  apart,  therefore,  from  its  industrial  aspect, 
organic  chemistry  must,  from  the  purely  scientific  point  of  view, 
always  be  regarded  as  a  branch  of  science  of  the  very  highest 
interest  and  importance. 

If  the  record  of  our  universities  is  examined,  it  is  at  once 
obvious  that  many  of  these  famous  places,  and  more  particularly 
the  universities  of  Oxford  and  Cambridge  and  the  Scottish 
universities,  contributed  practically  nothing  to  the  advancement 
of  organic  chemistry  during  the  latter  part  of  the  last  century, 
and  their  output  of  research  in  this  subject  is  still  far  less  than  it 
ought  to  be.  It  is  difficult  to  understand  why  our  universities 
should  so  persistently  hold  aloof  from  progress,  and  should  so 
often  entirely  fail  to  gauge  the  importance  of  leading  the  way  in 
new  developments,  on  which,  after  all,  in  many  cases  the  welfare 
of  the  country  depends.  How  very  different  is  the  picture 
exhibited  by  the  attitude  of  the  German  universities  towards 
organic  chemistry  during  the  critical  period  I  have  mentioned  ! 

So  soon  as  the  importance  of  organic  chemistry  became 
apparent,  great  teachers,  such  as  Liebig  and  Wohler,  Kekul6 
and  Baeyer,  founded  schools  specially  devoted  to  the  subject, 
and  they  and  their  pupils  then  began  to  publish  that  wonderful 
series  of  classical  investigations  which  laid  the  foundations  on 
which  the  superstructure  has  since  been  raised. 

The  value  of  the  example  of  these  great  teachers  and  of  the 
system  of  research  which  they  had  initiated  soon  became  generally 
appreciated  by  the  universities  in  Germany,  and  every  effort  was 
made,  bv  the  establishment  of  laboratories  supported  by  adequate 
grants  from  the  various  States,  to  help  forward  the  new  move- 


4i2         THE   BRITISH   COAL-TAR   INDUSTRY 

ment.  The  step  which,  in  my  opinion,  did  more  than  anything 
else  to  bring  about  the  wonderful  development  of  organic 
chemistry  in  Germany  was  the  provision  that  research  must  be 
an  essential  part  in  the  training  of  every  German  student  of 
chemistry. 

In  almost  every  direction,  and  to  a  far  greater  extent  than  has 
been  the  case  in  any  other  country,  Germany  has  recognised  the 
value  of  the  closest  possible  contact  between  the  industries  and 
the  universities.  In  Germany  the  majority  of  the  Professors  and 
Privatdocenten  are  in  close  touch  with  the  large  factories,  and 
spend  part  of  their  time  in  solving  technical  problems  which  they 
either  devise  themselves  or  which  may  be  submitted  to  them  by 
the  manufacturer. 

I  have  it  on  the  authority  of  several  of  the  best-known 
directors  of  German  works  that  the  atmosphere  of  the  university 
laboratory  is  much  more  suitable  for  discovery  than  that  of  the 
works,  and  that,  as  a  fact,  many  of  the  most  valuable  discoveries 
which  subsequently  proved  to  be  of  the  highest  technical  im- 
portance have  been  made  in  university  laboratories  and  transferred 
to  the  works  as  the  result  of  the  intimate  connection  I  have  just 
described.  Moreover,  when  it  is  remembered  that  the  important 
dyes,  malachite  green,  the  phthaleins,  artificial  alizarin,  and  in- 
digo, and  the  pharmaceutical  products  antifebrin  and  antipyrine, 
to  mention  only  a  very  few  cases,  were  discovered  in  university 
chemical  laboratories,  it  is  quite  clear  that  there  is  much  truth 
in  the  statement  of  the  works  directors.  Close  association  of 
the  universities  with  the  industries  does  not  exist  to  any  extent 
in  this  country,  and  is  one  of  the  things  we  have  to  aim  at  in 
the  future,  however  distasteful  this  may  appear  to  some  of  our 
academic  circles.  Systems  of  training  and  methods  of  teaching 
which  may  have  been  useful  centuries  ago,  but  have  become 
antiquated,  must,  in  these  days  of  acute  competition,  give  place 
to  methods  that  are  more  in  accordance  with  existing  requirements 
and  the  practice  of  other  nations  ;  otherwise  we  are  bound  to 
fall  behind  in  the  race. 

It  must,  I  take  it,  be  assumed  that  the  aim  of  the  university 
is  to  acquire  the  best  scientific  ability  for  its  professoriate  and 
teaching  staff,  and  therefore  the  home  of  the  best  scientific  re- 
search talent  must  always  be  the  university  laboratory  ;  it  is  there- 
fore quite  clear  that  close  association  between  these  laboratories 
and  the  works  must  be  of  great  advantage  to  industry.  Such  a 


THE   ORGANIC   CHEMICAL   INDUSTRY       413 

connection  cannot  fail  to  be  of  great  value  also  to  the  university, 
for  it  must  result  in  the  manufacturer  taking  a  keen  interest  in 
the  welfare  of  the  department  with  which  he  is  associated  ;  he 
will  willingly  provide  material  from  his  works  for  teaching  and 
research,  and  subscribe  liberally  to  the  resources  of  the  depart- 
ment, and  no  scientific  laboratory  —  chemical,  physical,  or 
engineering — can  do  good  work  unless  it  is  liberally  supplied 
with  material  and  funds. 

It  has  often  been  suggested  to  me  that  a  professor  who  is 
engaged  in  solving  problems  of  a  technical  nature  will  have  no 
time  for  other  scientific  research  work,  and  that,  since  results  of 
technical  value  must  often  be  kept  secret  and  may  never  be 
published,  the  reputation  of  his  department  will  suffer.  Ex- 
perience shows,  however,  that  such  is  not  the  case,  for  there 
is  little,  if  any,  diminution  in  the  output  of  research  work  in 
pure  science  from  the  German  laboratories  as  the  result  of  this 
system. 

We  must,  I  think,  agree  that  one  of  the  main  reasons  for  the 
rise  and  development  of  the  German  chemical  works  is  the 
appreciation  on  the  part  of  the  manufacturer  of  the  value  of 
science  in  connection  with  industry,  and  the  recognition  of  the 
great  importance  of  a  close  alliance  between  the  works  and  the 
research  laboratories  of  the  universities  and  leading  technical 
institutions  of  the  country. 

My  view  is  that  contact  with  the  research  department  of  a 
large  works  must  always  be  stimulating ;  problems  are  en- 
countered, many  of  them  of  great  scientific  interest,  which  would 
never  suggest  themselves  in  strictly  academic  circumstances  ;  and 
as  one  of  the  results,  the  tendency,  which  is  always  present  under 
existing  university  conditions,  for  the  professor  to  become  an 
academic  fossil  and  unproductive  is  postponed.  Again,  we  are 
all  aware  how  difficult  it  often  is  to  find  suitable  research  subjects 
for  the  budding  chemists  under  our  charge,  and  contact  with  the 
research  departments  of  a  flourishing  works  cannot  fail  to  suggest 
subjects  for  investigation  which  are  eminently  suitable  to  occupy 
the  attention  of  young  men,  many  of  whom  will  ultimately  take 
up  technical  work.  I  look  forward  to  the  time  when  the  scientific 
staffs  of  our  universities  and  technical  schools  will  not  only  be 
available  for  industrial  research,  but  will  be  encouraged  by  those 
in  authority  to  undertake  such  work  ;  for  1  am  quite  certain, 
and  indeed  it  is  very  generally  admitted,  that  the  association 


4H         THE   BRITISH   COAL-TAR   INDUSTRY 

of  the  best  academical  talent  in  the  country  with  the  technical 
laboratories  of  the  works  can  only  be  of  the  highest  mutual 
benefit. 

After  all,  this  kind  of  thing  is  quite  common  in  the  case  of 
the  engineering  departments  of  our  universities  and  technical 
schools  ;  and  if  the  system  works  well  in  the  case  of  engineering, 
there  is  surely  no  reason  why  it  should  not  be  equally  successful 
in  the  case  of  chemistry. 

Our  competitors  have,  from  time  to  time,  given  their  opinion 
as  to  the  reasons  for  the  transference  of  the  organic  chemical 
industry  from  this  country  to  Germany,  and,  as  such  views 
cannot  fail  to  be  instructive,  it  will  not  be  out  of  place  if  I  quote 
one  such  utterance.  On  the  occasion  of  the  jubilee  or  the 
discovery  of  mauve,  in  1905,  Dr  Duisberg,  one  of  the  best- 
known  directors  of  the  colour  works  of  Bayer  &  Co.,  in  Elberfeld, 
went  fully  into  this  question,  and  I  propose  to  read  a  few  extracts 
from  his  remarks  which  have  a  special  bearing  on  this  matter. 
Dr  Duisberg  said  :  "  You  inquire  further,  and  wish  to  know 
how  it  is  that  the  German  soil,  in  which  the  coal-tar  colour 
industry  has  grown  so  powerful,  varies  from  English  soil ;  what 
particular  conditions  were  there  which  had  been  so  advantageous 
for  its  fructification  ;  whether  it  was  not  eventually  possible  to 
produce  artificially  the  same  conditions  also  in  England,  and 
that  here  also  in  the  land  of  its  birth  those  rich  and  golden  fruits 
could  not  be  gathered,  the  harvest  of  which  is  reaped  by  Germany 
year  by  year.  I  do  not  believe  in  such  acclimatisation  in  England, 
at  least  for  the  present.  No  other  industry  requires  so  much 
uniformity  of  thought  and  action,  science  and  practice,  as  organic 
chemistry  and  the  organic  chemical  industry. 

"In  Germany,  not  only  has  chemical  science  developed  to  a 
considerable  extent,  but  at  the  same  time  the  technique  of  organic 
chemistry  has  flourished.  Both  have  stimulated  and  vitalised 
each  other,  and  both  have  supported  each  other.  Such  was  not 
the  case  in  England.  Although  the  Englishman  is  in  general 
practical,  he  is  wanting  in  that  peculiar  quality  which  we 
Germans  are  remarkable  for — that  is,  not  perseverance,  but 
patience  and  the  power  of  waiting  for  success.  For  all  the 
Englishman  does  he  expects  soon  to  be  compensated  in  hard 
cash." 

Continuing,  Dr  Duisberg  used  the  following  words,  which 
are  particularly  interesting  in  view  of  the  present  crisis  :  "But 


THE   ORGANIC   CHEMICAL   INDUSTRY      415 

you  will  say,  when  the  problems  have  been  solved,  and  when  the 
patents  have  run  out  and  the  manufacture  is  free  to  everyone, 
c  Why  should  not  the  English  and  foreign  works  decide  to  cope 
with  the  German  firms  and  compete  against  them  ? ' 

"In  my  opinion  this  would  be  futile,  and  would  be  of  no 
avail.  Even  in  Germany,  where,  as  we  have  seen,  the  conditions 
are  the  most  favourable,  it  would  now  be  scarcely  possible,  or 
at  least  be  a  singular  coincidence  if  a  manufacturer,  although 
possessed  of  energy  and  capital,  should  succeed  in  building  up  a 
new  firm  in  the  colour  line  so  as  successfully  to  compete  against 
the  existing  powerful  works.  Whereas,  therefore,  the  conditions 
in  England  for  many  industries,  such  as  for  the  mining  industry, 
for  spinning  and  weaving,  not  forgetting  inorganic  chemistry,  are 
far  more  advantageous  than  in  Germany,  the  latter  country  has 
the  natural  privilege  in  the  organic  chemical  industry,  and  other 
nations  should  not  envy  her  in  this,  but  leave  it  to  her." 

It  is  because  we  have  acted  in  the  manner  recommended  by 
Dr  Duisberg,  and  have  left  the  coal-tar  colour  industry  to 
Germany,  that  we  find  ourselves  in  the  present  grave  and  serious 
position. 

Views  similar  to  those  of  Dr  Duisberg  have  been  expressed 
in  many  quarters,  and  Lord  Moulton,  speaking  at  the  Royal 
Society  of  Arts  on  3rd  December  of  last  year,  gives  an  example 
which  is  also  very  much  to  the  point.1  "  I  read,"  he  said,  "  the 
other  day  with  bitter  feelings  the  address  of  one  of  the  ablest 
industrial  chemists  in  the  world — the  head  of  one  of  the  German 
chemical  industries — who,  talking  about  this  very  subject,  said  : 
'  England  talks  not  only  of  holding  her  own  in  the  war,  but  of 
beating  us  in  the  chemical  industry.  She  cannot  do  it,  because 
the  nation  is  incapable  of  the  moral  effort  of  taking  up  such  an 
industry,  which  implies  study,  concentration,  patience,  and  fixing 
the  eye  on  distant  consequences,  and  not  merely  on  the  monetary 
result.' '  Lord  Moulton  himself  puts  the  matter  in  this  way  : 
"  Some  fifty  years  ago  organic  chemistry  opened  up  a  domain  of 
industrial  wealth  that  he  could  only  compare  to  that  opened  up 
by  the  discovery  of  steam  power.  He  had  been  able  to  come  to 
but  one  conclusion — that,  either  from  being  too  well  off,  or  from 
sluggishness  of  intellect,  or  from  the  fact  that  the  capital  of  the 
country  had  passed  into  the  hands  of  people  who  were  unwilling 
either  to  learn  or  to  think,  England  had  abstained  almost  entirely 

1  See  p.  347,  ante. 


4i 6         THE   BRITISH   COAL-TAR   INDUSTRY 

from  an  attempt  to  reap  the  rich  harvest  open  to  the  industrial 
world  by  the  advance  of  organic  chemistry."  In  his  address 
delivered  in  the  Town  Hall,  Manchester,  on  8th  December  1914, 
Lord  Moulton  said  :  "  Gentlemen,  we  have  to  look  the  truth  in 
the  face.  It  (the  loss  of  the  coal-tar  colour  industry)  was  for  no 
other  reason  than  that  the  English  dislike  study.  The  English- 
man is  excellent  in  making  the  best  of  the  means  at  his  disposal, 
but  he  is  almost  hopeless  in  one  thing.  He  will  not  prepare 
himself  by  intellectual  work  for  the  task  that  he  has  to  do.  Now 
there  is  the  cause  and,  so  far  as  is  material,  the  sole  cause  of  the 
German  supremacy.  Is  that  a  cause  which  must  permanently 
operate  ?  The  answer  is,  of  course,  '  No.'  But  it  is  for  us  to 
reform  ourselves  ;  otherwise  no  relief  can  come."  * 

I  have  ventured  to  read  these  short  extracts  because  they 
contain  the  gist  of  the  matter,  and  because  I  cannot  think  of  any 
words  which  might  describe  the  position  better. 

If,  then,  we  accept  the  enormous  technical  importance  of 
organic  chemistry,  and  recognise,  as  Lord  Moulton  puts  it,  that 
the  industry  is  so  vast  that  it  can  only  be  compared  with  that 
opened  up  by  the  discovery  of  steam  power,  and  if  we  decide 
that  we  are  not  going  to  allow — as  Dr  Duisberg  suggests  that  we 
should — all  this  wealth  and  prosperity  to  pass  entirely  into  the 
hands  of  a  foreign  country,  what  course  must  our  manufacturers 
adopt  in  order  to  get  a  share  of  this  ?  I  have  already  said,  and 
everyone  will  agree,  that  they  must,  in  the  first  place,  make  up 
their  minds  so  to  conduct  their  works  that  research  is  going  on 
unceasingly  ;  no  works  can  possibly  flourish  which  is  content  to 
manufacture  only  well-known  colours,  and  it  is  only  by  the  dis- 
covery of  new  colours  and  other  products  that  manufacturers  can 
hope  to  get  a  satisfactory  return  on  their  capital.  The  manu- 
facturer must  therefore  see  that  his  laboratories  are  properly 
equipped,  and  well  supplied  with  research  chemists  of  ability, 
who  have  had  a  sound  scientific  training,  and  also  some  ex- 
perience in  the  methods  of  research.  All  this,  however,  will 
avail  little  unless  he  has  a  scientific  leader  in  his  works  who  is 
able  to  direct  the  investigations  of  his  young  staff  in  the  right 
channels. 

Students  of  mine  who  have  entered  chemical  works  have 
frequently  complained  to  me  that  there  is  no  one  over  them 
qualified  to  direct  their  investigations,  and  that  original  work 

1  See  p.  351,  ante. 


THE   ORGANIC   CHEMICAL   INDUSTRY      417 

seems  to  be  considered  of  secondary  importance,  and  only  to  be 
indulged  in  when  there  is  nothing  else  in  the  works  to  occupy 
the  attention  of  the  chemist. 

So  far  as  I  am  aware,  there  is  not  a  single  colour  works  in 
this  country  which  has  a  really  brilliant  scientific  head — by  which 
I  mean  a  chemist  of  wide  scientific  experience,  and  with  the 
knowledge  and  ability  to  direct  research  ;  and  this  is  a  very 
serious  state  of  things,  and  quite  incompatible  with  chemical 
efficiency. 

I  have  long  thought  that  the  want  of  an  able  scientific  head  is 
one  of  the  most  obvious  reasons  why  our  colour  works  are  in  such 
an  unsatisfactory  condition.  The  success  of  a  business  based  on 
science  must  often  be  essentially  the  work  of  a  single  brilliant 
scientific  man,  just  as  the  success  of  a  great  school  rests  with  the 
headmaster,  and  the  reputation  of  a  university  laboratory  depends 
on  the  ability  of  the  professor. 

If  a  works  is  fortunate  enough  to  have  the  services  of  a 
distinguished  scientific  man,  capable  of  initiating  and  carrying 
out  original  investigations,  and  who  will  not  only  be  constantly 
making  discoveries  himself,  but  be  able  at  the  same  time  so  to 
influence  his  young  staff  that  they  will  follow  in  his  footsteps, 
the  success  of  such  a  works  can  never  be  in  doubt.  I  am  afraid, 
however,  that  it  will  be  a  long  time  before  we  can  hope  that  our 
manufacturers  will  give  up  their  old-fashioned  rule-of-thumb 
methods  and  fully  grasp  the  truth  of  this  vital  matter. 

My  experience  of  the  manufacturer  in  this  country  is  that  he 
is  usually  merely  a  commercial  person  who  does  not  like  the 
expert,  and  especially  the  idea  of  giving  the  expert  a  prominent 
position  in  the  control  of  his  works.  Possibly  the  reason  in 
many  cases  is  ignorance  of  the  value  of  science,  but  more  prob- 
ably it  is  due  to  the  fact  that,  being  ignorant  of  science  himself, 
he  feels  that  if  the  expert  is  given  too  much  prominence  he 
must  either  study  himself  in  order  to  understand  the  expert  or 
leave  the  essential  control  of  the  business  in  his  hands.  Both 
these  courses  are  distasteful  to  the  ordinary  commercial  member 
of  a  board  of  directors  ;  the  expert  is  therefore  relegated  to  the 
background,  and  the  business  comes  to  grief. 

It  would  seem  to  be  scarcely  necessary  to  point  out  that,  if 
a  chemical  works  is  to  be  successful,  the  first  essential  is  that  it 
must  be  under  chemical  control,  and  that  every  department  must 
be  in  the  hands  of  an  expert ;  the  board  of  directors  may  then 

27 


4i 8         THE   BRITISH    COAL-TAR   INDUSTRY 

be  a  mixed  board,  provided  that  steps  are  taken  to  ensure  that 
chemical  opinion  is  largely  represented  on  it.  The  recognition 
of  the  soundness  of  this  principle  is  one  of  the  main  reasons  for 
the  success  of  the  German  works. 

Anyone  who  has  had  the  opportunity  of  visiting  the  principal 
German  colour  works,  as  I  have,  cannot  fail  to  have  noticed  that 
chemical  control  is  everywhere  ;  the  heads  of  departments  are 
always  chemists,  and  the  board  of  management  invariably  includes 
a  large  proportion  of  the  abler  chemical  experts  employed  in  the 
works.  Not  only  do  German  business  men  understand  that  the 
control  of  a  chemical  works  must  be  in  the  hands  of  the  chemist, 
but  they  are  also  careful  to  remunerate  their  chemists  liberally 
and  to  give  them  a  share  in  any  new  development  they  may 
initiate,  with  the  result  that  many  of  their  leading  chemists  are 
in  receipt  of  salaries  quite  unheard  of  in  this  country. 

When  we  ask  the  question  whether  we  can  adopt  methods 
of  a  similar  kind  in  this  country  we  find  ourselves  at  once  face 
to  face  with  very  grave  difficulties.  Let  us  assume  that  the 
necessity  for  the  chemical  control  of  a  chemical  works  is  conceded, 
as  conceded  it  must  be,  and  that  it  is  clearly  understood  that  the 
next  step  is  the  discovery  of  improvements  in  every  direction, 
such  as  the  invention  of  dyes  better  than  those  already  known, 
and  the  economical  development  of  essential  existing  processes, 
then  the  first  thing  to  be  done  will  be  for  our  universities  to  set 
to  work  to  educate  a  supply  of  organic  research  chemists  who 
will  be  able  to  undertake  this  work.  This  will  mean  that 
organic  chemistry  will  have  to  flourish  to  a  much  greater  extent 
than  it  does  now,  because  the  supply  of  organic  research  chemists 
available  under  ordinary  conditions  is  a  very  small  one,  and 
scarcely  sufficient  to  meet  even  the  moderate  demand  which  exists 
at  the  present  time. 

If  the  effort  gradually  to  develop — it  is  not  a  question  of 
immediately  establishing — a  thriving  organic  chemical  industry 
in  this  country  is  to  be  seriously  taken  in  hand,  and  not  to  be 
merely  talked  about,  and  if  the  requisite  capital  is  forthcoming, 
it  is  obvious  that  what  will  be  required  before  everything  else  will 
be  a  really  able  chemical  staff,  and  there  should,  therefore,  be  a 
great  opening  in  the  near  future  for  young  organic  chemists  of 
ability.  It  is  unfortunate  from  this  point  of  view  that  many, 
probably  the  large  majority,  of  our  young  chemists  are  not 
immediately  available,  since  most  of  them  are  at  present  engaged 


THE   ORGANIC   CHEMICAL   INDUSTRY      419 

in  military  service,  and  therefore  the  evolution  of  an  efficient 
chemical  staff  will  be  no  easy  matter.  A  small  beginning  may 
have  to  be  made,  but,  if  the  manufacturer  will  continually  bear 
in  mind  that  chemical  efficiency  must  always  be  the  basis  of  all 
his  calculations,  there  is  no  reason  to  doubt  that  success  will 
come  in  the  end,  even  though  it  may,  and  probably  will,  be  very 
slow  at  first. 

Soon  after  the  outbreak  of  the  war,  the  critical  position  brought 
about  by  the  shortage  of  the  dyes  which  are  vital  to  both  the 
cotton  and  wool  trades,  and  the  impossibility  of  importing  further 
supplies  from  abroad,  called  for  immediate  attention.  Urgent 
representations  from  dyers  and  calico-printers  and  others  engaged 
in  trades  which  require  large  supplies  of  dyes,  forced  the  Govern- 
ment to  see  that  something  must  be  done,  and  done  as  quickly 
as  possible,  to  find  a  solution  for  the  extraordinary  situation  that 
had  arisen.  A  Board  of  Trade  Committee  was  therefore  appointed 
on  25th  August,  with  the  Lord  High  Chancellor  (Viscount 
Haldane)  as  chairman,1  with  instructions  to  consider  the  best 
means  of  obtaining  for  the  use  of  British  industry  sufficient 
supplies  of  chemical  products,  and,  after  hearing  the  evidence 
of  many  of  the  more  important  producers  and  consumers,  a  small 
committee,  of  which  Professors  Meldola  and  Green  and  I  were 
members,  was  charged  with  the  task  of  sifting  the  mass  of  evi- 
dence which  had  come  forward  from  all  quarters. 

The  chairman  of  this  sub-committee  —  Lord  Moulton — 
devoted  a  great  amount  of  his  time  and  energy  and  experience 
of  German  industrial  conditions  to  the  task  of  interviewing  repre- 
sentatives of  the  industries  which  were  affected  by  the  stoppage 
of  supplies  from  Germany,  and,  as  the  result  of  the  report  of  the 
sub-committee  to  the  larger  body,  a  meeting  of  representatives 
of  industrial  firms  and  associations  was  held  on  loth  December 
at  the  Board  of  Trade,  when  the  following  resolution  was  passed 
unanimously  :  "  That  this  meeting  approves  in  principle  of  a 
national  effort  being  made  by  the  trade  to  increase  the  British 

1  The  other  members  of  the  committee  were  Mr  John  Anderson,  Dr  George 
Thomas  Beilby,  F.R.S.,  Prof.  James  Johnston  Dobbie,  F.R.S.,  Mr  David 
Howard,  Mr  Ivan  Levinstein,  Prof.  Raphael  Meldola,  F.R.S.,  Mr  Max 
Muspratt,  Prof.  William  Henry  Perkin,  F.R.S.,  Mr  Milton  S.  Sharp,  Sir  Arthur 
J.  Tedder,  Mr  Joseph  Turner,  and  Mr  Thomas  Tyrer,  with  Mr  Frank  Gossling, 
B.Sc.,  as  secretary.  Prof.  Arthur  George  Green,  M.Sc.,  was  subsequently 
added  to  the  committee. 


420         THE   BRITISH   COAL-TAR   INDUSTRY 

supply  of  synthetic  colours,  and  welcomes  the  assistance  of  His 
Majesty's  Government  for  that  purpose."  A  committee1  was 
appointed,  and  shortly  afterwards  recommended  a  scheme  which 
involved  the  formation  of  a  joint-stock  company,  having  for  its 
object  the  manufacture  and  supply  of  synthetic  colours.  Subse- 
quently the  Government  announced  that  they  were  prepared  to 
assist  such  an  effort  in  the  following  way  :  "  If  a  limited  Company 
were  formed  on  co-operative  lines  with  a  share  capital  of 
£3,000,000,  the  Government  agree  to  advance  to  such  Company 
£1,500,000,  bearing  interest  at  the  rate  of  4  per  cent,  per  annum, 
and  secured  as  a  first  charge  on  the  assets  and  undertaking  of 
the  Company,  and  to  be  repayable  in  twenty-five  years."  The 
important  proviso  was,  however,  made  that  "  the  interest  on  the 
advance  and  a  sinking  fund  for  the  repayment  are  to  be  payable 
only  out  of  the  net  profits  of  the  Company,  but  are  to  be  cumu- 
lative." When  this  scheme  was  made  public  its  reception  was 
not  cordial,  and  the  application  for  shares  fell  far  short  of  what 
had  evidently  been  expected  by  its  promoters.  In  explanation 
of  this  it  should,  in  the  first  place,  be  quite  clearly  pointed  out 
that  neither  the  Board  of  Trade  Committee  nor  the  sub-com- 
mittee had  anything  whatever  to  do  with  the  preparation  of  the 
scheme,  and  it  is  certainly  extraordinary  that  a  committee 
consisting  entirely  of  business  men,  and  which  did  not  include 
a  single  chemical  expert,  should  have  been  entrusted  with  the 
formulation  of  a  scheme  for  the  founding  and  developing  of  a 
chemical  industry.2 

Had  a  chemical  expert  been  present  I  venture  to  think  that 
such  a  scheme  would  never  have  been  placed  before  the  public. 
It  is  stated  in  the  memorandum  of  agreement  attached  to  the 
scheme  that  the  Company  had  been  incorporated  for  the  purpose, 
among  other  things,  of  manufacturing  and  selling  dyes,  colours, 
and  other  chemical  substances,  which,  previously  to  the  war, 
were  exclusively  or  principally  manufactured  in  Germany,  and 
no  mention  is  made  of  what  ought  to  be  the  main  object  of  such 
a  Company,  namely,  the  employment  of  a  large  staff  of  research 

1  The  committee  appointed   was  Messrs   Lennox   Lee  (Calico-Printers' 
Association),  Milton  S.  Sharp  (Bradford  Dyers'  Association),  H.  W.  Christie 
(United  Turkey-Red   Company),   Chas.    Diamond   (English   Sewing-Cotton 
Company),    G.   Marchetti  (John   Crossley  &   Sons),  and  R.   D.   Pullar  (J. 
Pullar  &  Sons). 

2  Compare  Prof.  Meldola's  admirable  letter  in  the  Times  of  loth  January. 


THE   ORGANIC   CHEMICAL   INDUSTRY      421 

chemists  under  leaders  of  ability  for  the  purpose  of  making  new 
discoveries  in  every  possible  direction. 

It  cannot  be  too  strongly  emphasised  that  it  is  not  merely  a 
question  of  producing  the  dyes  which  are  required  during  the 
war ;  any  company  which  is  formed  must  be  established  in  so 
strong  a  position  that  it  can  expect  to  deal  successfully  with  the 
keen  competition  which  will  be  waged  with  the  greatest  severity 
by  the  Germans  after  the  war. 

The  promoters  of  the  scheme  do  not  appear  to  have  appreciated 
the  difficulties  of  the  situation,  and  obviously  think  that  the 
manufacture  of  dyes  in  this  country  which  previous  to  the  war 
had  been  invented  and  produced  in  Germany  is  a  matter  which 
can  quite  easily  be  managed. 

It  seems  to  be  imagined  in  many  quarters  that,  in  order  to 
manufacture  a  dye  which  had  previously  been  made  in  Germany, 
all  that  is  necessary  is  to  follow  the  directions  given  in  the  patent 
dealing  with  that  particular  dye.  No  greater  mistake  could 
possibly  be  made.  It  is  common  knowledge  that  German  manu- 
facturers have  for  many  years  devoted  large  sums  to  the  estab- 
lishment of  an  efficient  staff  of  patent  experts,  whose  business  it 
is  so  to  word  a  patent  that,  whilst  it  satisfies  the  requirements 
of  the  patent  laws  of  the  various  countries  in  which  it  is  taken 
out,  only  gives  such  information  as  is  absolutely  necessary,  and 
contains  no  indication  of  the  process  which  is  used  in  the  actual 
manufacture.  In  many  cases  patents  are  devised  which  are  of  no 
practical  value,  and  are  merely  intended  to  mislead  and  throw 
competitors  on  the  wrong  scent.1  The  discovery  of  the  most 
efficient  method  of  working  patented  processes  is  therefore  often 
a  matter  of  great  experimental  difficulty,  and  may  require  many 
months  of  research.  Any  new  Company  started  with  the  object 
of  manufacturing  dyes  which  previously  to  the  war  had  been 
made  exclusively  in  Germany  must  therefore  be  prepared  to 
employ  a  large  staff  of  research  chemists  for  a  long  period  without 
any  prospect  of  return  in  the  way  of  dividends. 

Further,  it  must  always  be  remembered  that  the  Germans 
have  many  years'  start  of  the  new  Company,  and  have  accumu- 
lated such  vast  experience  of  methods  of  manufacture,  and  more 
particularly  of  the  recovery  and  economical  use  of  by-products, 
that  they  are  able  to  sell  at  a  profit  at  very  low  prices.  What 

1  This  point  is  well  dealt  with  by  Prof.  Jocelyn  Thorpe,  F.R.S.,  in  a  letter 
to  the  Times  of  2nd  February. 


422         THE   BRITISH   COAL-TAR   INDUSTRY 

the  new  Company  has  to  face  is,  therefore,  in  the  first  place,  the 
problem  of  working  out  methods  of  manufacture  and  the  utilisa- 
tion of  by-products  until  they  have  arrived  at  the  same  state  of 
efficiency  as  the  Germans,  and  that,  it  seems  to  me,  may  be  a 
matter  of  years.  While  this  is  being  done,  the  new  Company 
must  also  be  busily  engaged  in  training  a  large  body  of  research 
chemists  under  the  supervision  of  capable  scientific  leaders,  so 
that  the  works  may  develop  in  as  many  new  directions  as  possible, 
because  the  Company  can  only  hope  for  permanent  success  if  it 
pursues  a  policy  of  discovery  and  invention.  Another  point  has 
also  to  be  borne  in  mind,  and  that  is  that  the  Germans  supply 
dyes  and  other  products,  not  only  to  this  country,  but  to  practi- 
cally all  the  other  nations,  and,  in  the  event  of  a  new  Company 
being  formed  on  such  large  lines  that  it  might  prove  to  be  a 
serious  competitor,  a  German  works  could  well  afford  to  sell  at 
cost  price  or  at  a  loss  in  this  country  and  make  its  profits  in  other 
lands  until  the  new  Company  had  been  ruined.  Lastly,  if  we 
are  to  be  allowed  to  make  dyes,  etc.,  during  the  war  according 
to  patents  belonging  to  the  Germans,  what  is  to  happen  after  the 
war  ?  Will  the  Company  be  still  allowed  to  use  these  patented 
processes,  or  will  the  patents  again  become  the  sole  property  of 
the  Germans,  and  be  workable  in  this  country  only  on  the 
payment  of  royalties  or  licences  ?  This  matter  has,  no  doubt, 
been  carefully  considered  by  the  law  advisers  of  the  Government, 
but,  so  far  as  I  know,  no  authoritative  statement  has  been  issued 
which  makes  this  situation  clear.1 

1  Mr  Runciman  made  the  following  reference  to  this  important  point  in 
Parliament  on  23rd  February  last : — 

"  The  success  of  the  concern  would  depend  largely  on  the  way  in  which  the 
German  patents  were  administered.  The  Act  passed  last  autumn  as  an 
emergency  measure  provided  that  the  operators  of  German  patents  in  this 
country  should  have  a  full  chance  of  conducting  them  under  licence,  and  it  was 
the  intention  of  the  Government  not  to  cripple  this  Company  when  the  war  was 
over,  but  to  give  them  every  opportunity  of  making  the  most  of  German  patents. 
They  would  leave  over  for  discussion  as  between  Germany  and  this  country  the 
payment  of  royalty  in  respect  of  these  patents.  There  were  English  patents  in 
Germany  on  which  he  hoped  a  royalty  was  being  paid  there.  We  should  hand 
over  these  royalties  if  Germany  would  bargain  fairly  with  us.  But  the  operating 
of  these  patents  which  would  be  undertaken  by  the  new  Company  would  pro- 
ceed after  the  war  was  over,  without  interruption  and  without  hindrance." 

If  this  statement  means  that,  besides  the  arduous  task  of  competing  with 
the  well-established  German  works,  the  new  Company  may  also  have  to  pay 
royalties  or  licences  to  those  works,  then  it  is  obvious  that  the  difficulties  of 
the  situation  will  be  greatly  accentuated. 


THE   ORGANIC   CHEMICAL   INDUSTRY       423 

Although  it  is  a  matter  of  so  much  congratulation  that  the 
Government,  which  in  past  years  has  paid  practically  no  attention 
to  science  and  the  application  of  science  to  industry,  should,  at 
last,  have  recognised  the  necessity  for  intervening  and  in  no 
uncertain  fashion,  I  have  been  forced  to  the  conclusion,  largely 
for  the  reasons  which  I  have  just  stated,  that  the  Company 
founded  on  the  lines  of  this  first  Government  scheme  could  not 
be  expected  to  be  successful  in  achieving  the  object  which  we  all 
have  so  much  at  heart,  namely,  the  recovery  and  development  of 
the  organic  chemical  industry  in  this  country.  Since  the  applica- 
tion for  shares  in  the  proposed  Company  was  quite  insufficient, 
the  Government  withdrew  the  scheme,  and  substituted  for  it  an 
amended  proposal,  which  is  certainly  in  some  respects  an  im- 
provement.1 The  new  proposal  is  to  form  a  Company  with  a 
share  capital  of  only  £2,000,000,  towards  which  the  Govern- 
ment will  make  a  loan  for  twenty-five  years,  corresponding  with 
the  amount  of  the  share  capital  raised,  and  up  to  a  total  of 
£1,000,000. 

In  addition,  and  with  the  desire  to  promote  research,  the 
Government  have  undertaken  for  a  period  of  ten  years  to  make 
a  grant  to  the  Company,  for  the  purposes  of  experimental  and 
laboratory  work,  up  to  an  amount  not  exceeding  in  the  aggregate 
£100,000. 

This  amended  proposal  is  another  proof  of  the  determination 
of  the  Government  to  meet  the  criticisms  which  were  raised 
against  the  first  scheme  in  a  generous  spirit,  and  to  do  all  it 
possibly  can  to  assist  the  efforts  of  the  manufacturers  in  this 
country  to  place  the  organic  chemical  industry  on  a  firm  basis. 
If,  then,  I  make  certain  criticisms  of  the  new  proposal,  it  must  be 
clearly  understood  that  I  do  not  do  so  in  any  spirit  of  hostility 
to  the  scheme,  but  rather  in  the  hope  that  the  adoption  of  some 
modifications  in  the  proposals  may  make  the  scheme  workable 
and  more  likely  of  success.  In  the  first  place  I  hold  that  the 
scheme  must  be  considered  in  the  light  of  the  criticisms  which 
I  have  just  advanced  in  connection  with  the  first  Government 

1  The  members  of  the  enlarged  Committee  which  is  responsible  for  the 
second  scheme  are  Sir  A.  F.  Firth,  Bart.,  Sir  Frank  Hollins,  Bart,  Sir  Mark 
Oldroyd,  Mr  H.  W.  Christie,  Mr  J.  Clarkson,  Mr  Charles  Diamond,  Mr 
Kenneth  Lee,  Mr  G.  Marchetti,  and  Mr  R.  D.  Pullar ;  and,  in  spite  of  Prof. 
Meldola's  letter  and  other  letters  to  the  Press,  again  did  not  include  expert 
chemical  opinion. 


424        THE   BRITISH   COAL-TAR   INDUSTRY 

plan,  and  I  hope  that  these  points  will  be  clearly  handled  in  any 
detailed  statement  of  this  or  any  subsequent  scheme. 

There  are,  however,  other  matters  which  call  for  comment. 
The  grant  for  scientific  research  may  be  welcomed  as  a  satis- 
factory addition  to  the  old  proposal,  mainly  because  it  shows 
that  the  Committee  of  users  of  dyes  have  at  last  found  out 
that  research  is  necessary  if  the  new  Company  is  to  be  a  suc- 
cess. My  own  feeling,  however,  is  that  the  Company  ought 
to  provide  for  research  out  of  its  ordinary  capital  as  a  matter 
of  course,  and  should  not  require  a  special  subsidy  for  this 
purpose. 

A  much  better  plan,  I  venture  to  think,  would  be  to  employ 
this  grant  to  subsidise  the  research  laboratories  of  those  universi- 
ties and  technical  schools  which  are  willing  to  specialise  in  organic 
chemistry,  and  are  prepared  to  train  a  certain  number  of  research 
students  with  the  definite  view  of  their  subsequently  entering  the 
service  of   the   new    Company.     Supposing  the    new  Company 
were  to  adopt  the  view  which  I  have  urged  in  this  address,  that 
closer  connection  between  the  universities  and  the  industries  is 
most  desirable,  and  were  to  work  in  conjunction  with  the  staffs 
of  some  of  the  leading  organic  schools,  it  is  quite  obvious  that 
the  knowledge  of  the  needs  of   the  works  which  would  result 
from  this  connection  would  enable  the  staff  to  supply  research 
students   of   exactly   the    type    required   by   the   works.     Such 
research    students    would    have   been    trained   under   the    best 
scientific  supervision  which  the  country  can  provide,  and  at  the 
same   time   they   would   enter   the  works  with   a   considerable 
knowledge  of  the  application  of  organic  chemistry  to  technical 
operations,  and  be  in  a  position  to  tackle  with  success  research 
problems  connected  with  new  discoveries  and  new  developments 
in    the  works.     The  plan  of   training  research    students    under 
these  conditions  is,  as  I  have  already  pointed  out,  the  one  which 
has    long    been    adopted   with    such    extraordinary   success    in 
Germany,  and  the  large  subsidies  which  the  various  States  place 
at   the  disposal  of  their  universities  allow  of   the    purchase   of 
expensive   apparatus   and  appliances  which   are  outside  the  in- 
adequate resources   of   most   of   the    university  laboratories    of 
this  country. 

With  regard  to  the  kind  of  works  it  is  proposed  to  organise 
for  the  manufacture  of  dyestuffs,  etc.,  which  previous  to  the  war 
had  been  made  in  Germany,  it  would  be  well  carefully  to  consider 


THE   ORGANIC   CHEMICAL   INDUSTRY      425 

the  policy  which  the  Germans  have  adopted  with  so  much  success 
in  the  matter  of  the  construction  and  arrangement  of  their  works. 
I  think  that  one  of  the  things  which  must  strike  a  visitor  to  a 
great  German  works  more  perhaps  than  any  other  is  the  order 
and  cleanliness  which  reigns  everywhere,  and  the  obvious  care 
which  is  taken  that  every  manufacturing  operation  shall  be 
efficient  in  every  detail.  This  order  and  cleanliness  is  not  con- 
fined to  the  section  of  the  works  which  deals  with  organic  pro- 
ducts ;  the  same  state  of  things  is  to  be  observed  in  every  part, 
as,  for  example,  in  the  case  of  the  large  plants  which  deal  with 
the  manufacture  of  sulphuric  acid,  nitric  acid,  and  other  inorganic 
products.  Perhaps  the  idea  which  is  conveyed  most  vividly  by 
works  such  as  these,  all  of  which  are  concerned  with  the  manu- 
facture of  a  very  large  number  of  products  of  widely  differ- 
ent character,  is  that  they  are,  after  all,  merely  laboratories  on  a 
larger  scale. 

A  very  different  impression  is  got  by  an  inspection  of  many 
of  the  colour  works  in  this  country,  and  it  seems  to  me  very 
doubtful  policy  to  suggest  the  possibility  of  the  acquisition  of 
works  of  this  kind,  which  are  obviously  not  efficient,  and  could 
only  be  made  so  by  pulling  down  and  re-building.  It  may  be 
said  that  the  most  efficient  only  will  be  taken  over,  but  selection 
will  be  found  most  difficult,  because,  if  the  new  Company  proves 
a  success,  great  pressure  will  be  exerted  by  existing  works  in 
order  to  enter  the  charmed  circle,  and  the  argument  of  unfair 
competition  will  be  used  for  all  it  is  worth,  and  will  be  very 
difficult  to  deal  with.  Again,  it  is  most  important  not  to  lose 
sight  of  the  fact  that  the  experience  of  the  Germans  is  all  in 
favour  of  building  up  very  large  works,  and  against  spreading 
manufacturing  operations  over  small  works  situated  in  different 
parts  of  the  country. 

The  reason  for  this  is  obvious.  In  the  manufacture  of  any 
substance,  by-products  are  almost  always  produced  which  must 
either  be  recovered  or  used  in  the  manufacture  of  other  saleable 
products  ;  otherwise  serious  loss  is  inevitable.  It  is  exactly  in 
this  respect  that  the  Germans  are  so  efficient,  and  the  wonderful 
organisation  which  enables  them  to  dovetail  one  process  into 
another  is  one  of  the  reasons  why  the  comparatively  small  works 
in  this  country  find  it  impossible  to  compete  with  them  even  in 
the  manufacture  of  such  simple  substances  as  salicylic  acid  or 
/3-naphthol.  In  order  that  by-products  may  be  used  to  the  best 


426         THE   BRITISH   COAL-TAR   INDUSTRY 

advantage  it  is  obviously  essential  that  all  these  dovetailing 
operations  must  be  carried  out  on  the  same  site,  so  that  it  may 
not  be  necessary  to  transport  the  by-products  from  one  works  to 
another,  an  operation  which  could  not  fail  to  entail  loss.  Prob- 
ably the  best  course  for  the  new  Company  is  either  greatly  to 
enlarge  the  works  of  Messrs  Read  Holliday  &  Sons,  or,  if  it  is 
difficult  to  find  space  for  this  purpose  in  Huddersfield,  to  take 
steps  to  acquire  a  suitable  site  and  erect  and  equip  works  thereon, 
a  plan  which  is  mentioned  in  the  explanatory  statement  as  one  of 
the  objects  of  the  new  Company. 

Let  us  suppose  that,  in  the  near  future,  a  practically  new 
works  is  built  on  a  large  scale,  and  with  all  the  most  modern 
appliances,  and  that  the  control  of  the  whole  works  and  of  the 
different  departments  is  placed  in  the  hands  of  efficient  chemical 
leaders  with  adequate  staffs  of  chemists  under  their  charge,  and 
that  the  Company  has  also  large  and  well-equipped  research 
laboratories  busily  engaged  in  discovering  new  developments  and 
improvements  on  existing  processes  ;  what  prospect  has  such  a 
works  of  competing  successfully  with  the  existing  German 
organisations  and  of  obtaining  a  fair  share  of  the  organic  chemical 
industry  ? 

In  answering  this  important  question  it  must  again  be  empha- 
sised that  the  German  works  with  which  the  new  Company  must 
compete  are  enormous  organisations  controlling  almost  unlimited 
resources  and  in  a  most  flourishing  condition. 

The  Farbwerke,  vormals  Meister,  Lucius  &  Brtining,  in 
H5chst,  employs,  for  example,  350  chemists,  150  engineers  and 
technical  experts,  600  clerks,  and  about  10,000  workmen.  The 
probability  of  successfully  competing  with  several  organisations 
of  this  kind,  grouped,  as  they  are,  in  combines  in  order  the  more 
readily  to  be  able  to  crush  competitors  and  secure  the  monopoly 
of  the  industry,  also  depends,  no  doubt,  to  a  great  extent  on  the 
condition  of  the  German  chemical  industries  after  the  war.  If 
we  suppose  that  the  German  companies  will  continue  to  work 
with  the  same  efficiency  as  before,  or  will  rapidly  regain  that 
efficiency,  I  am  inclined  to  think  that  we  must  be  prepared  to 
face  the  certainty  that  some  years  must  elapse  before  we  can 
compete  successfully  against  organisations  which  have  taken 
years  to  develop  and  bring  to  perfection. 

Failure  to  develop  on  research  lines  is  scarcely  conceivable 
if  the  works  is  in  charge  of  a  highly  trained  chemical  staff,  but, 


THE   ORGANIC   CHEMICAL   INDUSTRY       427 

on  the  other  hand,  if  it  gets  into  the  power  of  the  business  man 
who  wants  an  immediate  return  for  his  outlay,  is  not  willing  to 
wait  for  results,  and  fails  to  appreciate  the  importance  of  scientific 
control,  then  no  tariff  can  avert  disaster.  I  am  sure  we  shall  all 
watch  the  course  of  events  with  the  greatest  interest,  and  hope 
that  the  new  venture  may  have  a  large  measure  of  success,  and 
bring  back  to  this  country  at  least  a  tithe  of  the  prosperity  which 
attaches  to  the  organic  chemical  industry. 


INDEX    OF    NAMES 


Abel,  F.  A.,  59,  75,  144,  158. 
Allhusen,  C.,  317. 
Anderson,  51,  52,  53,91,236. 
Anderson,  J.,  419. 
Arkwright,  284. 

Armstrong,  H.    E.,  69,    191,    192,    194, 
221,  222. 


Babbage,  284. 

Badische  Anilin-  und  Soda-Fabrik,  74, 
85,  94,  97,  119,  136,  190,  196,  198, 
199,  202,  205,  207,  208,  210,  219, 
220,  247,  248,  255,  257,  272,  301, 
308,  312,  320,  326,  327,  365,  368, 
382,  390. 

Baeyer,  A.,  50,  53,  74,  95,  97,  98,  122, 
123,  200,  204,  205,  207,  263,  264, 
265,272,315,  324,411. 

Bardy,  173,  174. 

Barlow,  T.,  148. 

Barnes,  W.  C.,  &  Co.,  135. 

Bayer,  F.,  &  Co.,  198,  210,  224,225,414. 

Beaconsfield,  Lord,  190. 

Beale,  241. 

Bechamp,  9,  77,  I53>  238. 

Beilby,  G.  T.,  419. 

Beilstein,  169. 

Berlin  Aniline  Co.,  198,  301. 

Bernthsen,  A.,  102,  131,  193,  224,  325. 

Berry,  A.  E.,  331. 

Berthelot,  51,  52. 

Berzelius,  315. 

Bessemer,  H.,  284. 

Besthorn,  127,  129. 

Bethels  Tar  Works,  146. 

Bindschedler  &  Busch,  365,  366. 

Bindschedler,  H.,  366,  367. 

Birkeland,  381. 

Black,  J.,  &  Co.,  78,  134- 

Bloxam,  A.  G.,  269,  279. 

Boettger,  382. 

Bottiger,  192. 

Bowrey,  J.  J.,  145- 

Boyle,  R.,  284. 


Bradford  Dyers'  Association,  197. 

Brandenburg,  63. 

Bretonniere,  194,  265. 

British  Alizarin  Co.,  135,  229,  290,  311, 
312. 

British  Cotton  and  Wool  Dyers'  Associa- 
tion, 197. 

Brooke,  Simpson  &  Spiller,  64,  126,  198, 
237,250,303,410. 

Brougham,  Lord,  398. 

Brown,  J.  T.,  145. 

Brunck,  H.,  204,  219,  221,  324,  326. 

Brunner,  J.  T.,  63. 

Brunner,  Mond  &  Co.,  388. 

Bunsen,  R.,  146. 

Burt,  Bolton  &  Heywood,  56,  117,  250. 

Burwell,  219. 


Cahours,  85,  147. 

Cain,  J.  C.,  243,  278,  294,  297. 

Calvert,  C.,  33. 

Caro,  H.,  12,  52,  58,  63,  74,  86,  89,  91, 
95,  98,  99,  H5,  122,  123,  125,  130, 
136,  148,  154,  168,  170,  178,  184, 
206,  242,  243,  246,  247,  248,  249, 
253,  255,  257,  262,  263,  264,  271, 
3oi,  303,  3i6,  324. 

Cartwright,  284. 

Cassal,  C.  E.,  333. 

Cassella,  L.,  &  Co.,  196,  198. 

Chapman,  A.  C.,  330. 

Chapman,  E.  T.,  61. 

Chapman,  Messel  &  Co.,  250,  255. 

Chapman,  S.,  190. 

Chapoteaut,  163. 

Chardonnet,  Count,  382. 

Chemische  Fabrik  Griesheim-Elektron, 
214. 

Cherpin,  29,  171. 

Christie,  H.  W.,  420,  423. 

Church,  A.  H.,  33,  35,  99,  147,  150. 

Clarkson,  J.,  423. 

Glaus,  129. 

Claus  &  R^e,  198. 


429 


430 


THE   BRITISH    COAL-TAR   INDUSTRY 


Clayton  Aniline  Co.,  198. 
Cliff,  146. 
Clowes,  F.,  145. 
Coblentz,  242. 
Coke,  Lord,  392. 
Coleman,  J.  B.,  301. 
Colin,  48,  53. 
Collas,  in. 
Coupler,  122. 
Cox  Bros.,  133. 
Crace-Calvert,  254. 
Croissant,  194,  265. 
Crookes,  W.,  145. 
Crum,  Walter,  &  Co  ,  134. 


Dale,  J.,  12,   52,  81,  99,  no,  154,  170, 

242,  301. 

Dalmonach  Print  Works,  155. 
Dalton,  284,  315. 
Darwin,  F.,  284. 
Davy,  H.,  284,  3I5- 
Davy,  J.,  89. 

Dawson,  Dan,  &  Co.,  301. 
Deacon,  214. 
Deering,  W.  H.,  145. 
De  Laire,  82,  84,  122,  159,  161,  163,243, 

253- 

De  .a  Rue,  158. 
De"pouilly,  P.  E.,  37,  241. 
Dewar,  J.,  118,  129,  138,  222,  284. 
Diamond,  C.,  420,  423. 
Diesbach,  380. 
Divers,  E.,  145. 
Dobbie,  J.  J.,  330,  419. 
Dobereiner,  29. 
Doebner,  O.,  63,  85,  262. 
Dower,  254. 
Dreaper,  W.  P.,  279. 
Drewsen,  W.,  207,  264. 
Duisberg,  C.,  282, 289,  292,  294,  325,  414, 

415,416. 

Dumas,  A.,  53, 91, 142, 146,  164,  236,  315. 
Duprey,  F.,  174. 
Dusart,  178. 


Emmerling,  205. 

Engler,  205. 

English  Sewing  Cotton  Co.,  197. 

Ewer  &  Pick,  131. 

Eyde,  381. 

Faraday,  M.,  5,  47,  53,  79,  109,  no,  123, 

141,  186,  235,  284. 
Farbenfabriken  Elberfeld  (see  F.  Bayer 

&  Co.). 


Farbwerke  Hoechst  (see  Meister,  Lucius 

&  Briining). 
Feilmann,  E.,  279. 
Fichte,  346. 
Field,  F.,  32. 
Filehne,  118,  119. 
Firth,  A.  F.,  423. 
Fischer,  E.,  60,  85,  86,  119,  125,  193,262, 

315,  320,  321,  324,  367,  370. 
Fischer,  O.,  60,  84,  85,  86,  11 8,  125,  126, 

127,  129,  262,  265,  324,  367. 
Fluerscheim,  382. 
Forster,  M.  O.,  348. 
Foster,  H.  A.,  310. 
Franc  Bros.,  241. 
Frankland,  P.,  379. 
Friswell,  R.  J.,  60,  69,  138. 
Fritsche,  4,  142,  187. 


Gallik,  97. 

Garden,  142,  235. 

Gardner,  W.  M.,  314,  371. 

Gay-Lussac,  315. 

Gessert  Freres,  57,  255. 

Geyger,  A.,  170,  175. 

Gilliard,  Monnet  &  Cartier,  207. 

Girard,  C.  H.,  82,  84,  122,  159,  161,  171, 

243,  253- 

Girard  and  De  Laire,  21,  22,  163. 
Glaser,  325. 
Gordon,  J.  W.,  389. 
Gossage,  W.,  317. 
Gossling,  F.,  419. 
Graebe,  C.,  46,  50,  52,  53,  56,  57,  63,  69, 

91,   93,    in,    122,  130,  177,   178, 

179,  183,  205,  245,  246,  247,  248, 

250,  262,  271,  302,  324. 
Graham,  C.,  70,  284. 
Grassier,  F.,  122. 

Green,  A.  G.,  189,  294,  323,  331,  419. 
Greenford   Green  Works   (see    Perkin 

&  Sons). 

Grey,  M.,  40,  155. 
Gness,  P.,  65,  69,  99,  115,  148,  167,  168, 

170,  254,  271,  301,  324. 
Gnmaux,  85. 
Guinon,  Marnas  &  Bonnet,  35,  80,  83, 

154. 
Guyot,  242. 


Haber,  320,  382. 
Haen,  de,  408. 
Haessermann,  382. 
Haldane,  Lord,  402,  419. 
Hall,  T.,  144,  145. 
Hanhart,  42. 


INDEX   OF   NAMES 


43 


Harrmann,  120. 

Harvey,  A.,  &  Son,  133. 

Henderson,  222,  340. 

Hepp,  E.,  193,  265. 

Heumann,  K.,  210,  211,  272. 

Heys,  Z.,  &  Sons,  134. 

Hickson,  E.,  132,  313. 

Higgin,  49. 

Hobrecker,  172. 

Hoff,  R.,  178. 

Hofmann,  A.  W.,  4,  6,  17,  20,  21,  23,  25, 
26,  27,  44,  45,  80,  81,  86,  100,  108, 
1 10,  126,  130,  142,  143,  145,  156, 
15%)  J595  J6o,  162,  164,  166,  167, 
169,  170,  171,  172,  174,  175,  176, 
177,  1 86,  187,  201,  211,  235,  236, 

242, 246, 253, 254,  262, 278,  300, 
301, 302, 316, 321, 324,  390. 

Hollins,  F.,  423. 
Holzmann,  167. 
Hoogewerff,  211. 
Howard,  D.,  419. 
Huxley,  T.  H.,  284. 

Jacobson,  E.,  176. 
Julius,  P.,  170. 

Kahlbaum,  408. 

Kalle  &  Co.,  208. 

Kay,  242. 

Kehrmann,  193. 

Keisser,  J.,  170. 

Keith,  T.,  &  Sons,  78,  152,  240,  300. 

Kekule,    50,  51,  53,  178,   185,  261,  262, 

268,  322,  324,  411. 
Kelvin,  Lord,  284. 
Kern,  A.,  89. 
Kirkham,  241. 
Knietsch,  R.,  213,  215. 
Knorr,  L.,  119. 
Koch,  J.  J.,  94,  249. 
Koechlin,  H.,  117,  118,  123. 
Kolbe,  34,  83. 
Kopp,  E.,  28,  164,  165. 
Korner,  G.,  129. 
Kostanecki,  193. 
Kiihlberg,  169. 

Laubenheimer,  325. 

Laurent,  37,  51,  53,  65,  91,  142,  146,  236. 

Lauth,  C,  29,  61,  84,  85,  171,  172,  241, 

244,  260,  262,  264. 
Le  Bel,  31 5. 
Le  Blanc,  380. 
Leckie  &  MacGregor,  133. 
Lee,  K.,  423. 


Lee,  L.,  420. 

Lefevre,  195. 

Leibius,  167. 

Leigh,  J.,  1 10. 

Leonhardt,  A.,  &  Co.,  198. 

Levinstein,  H.,  220. 

Levinstein,  I.,  117,  135,  200,  203,  275. 

Levinstein  Ltd.,  198,  390,  419. 

Liebermann,  C.,  46,  50,  52,  53,  56,  57,91, 
93,  in,  122,  177,  178,  183,  193, 
205,  245,  246,  247,  248,  250,  271, 
302,  324. 

Liebig,  29,  109,  1 10,  315,  411. 

Liggins,  140. 

Lightfoot,  J.,  254. 

Limpricht,  85. 

Linde,  C.,  381. 

Lowe,  254. 

Luynes,  de,  24. 


Macara,  C.  W.,  288,  377. 

M'Kendrick,  118. 

M'Leod,  162. 

Mansfield,  C.  B.,  6,  in,  123,  142,  158, 

187,  235,  236,  237,  242. 
Manson  &  Henry,  133. 
Marchetti,  G.,  420,  423. 
Martius,  35,  117,  169,  174,  253,  301. 
Maule,  253. 

Maw,  H.  W.,  350. 

Medlock,  H.,  18,  82,  121,  124,  157,  158, 

243,  253,  301. 
Meister,  Lucius  &  Briining,  68,  126,  136, 

198,  205    208,  308,  312,  365,  368, 

370,  426. 
Meldola,   R.,  64,  65,  68,  70,  121,  140, 

1 88,  191,  219,  220,  227,  228,  233, 
234,  257,  259,  284,  294,  322,  323, 
401,  406,  419,  420,  423. 

Mene,  99. 

Merck,  E.,  408. 

Messel,  R.,  190,  255,  348,  350. 

Michaud,  381. 

Michler,  89,  90. 

Miller  &  Co.,  153,  236. 

Mitchell,  W.  A.,  135. 

Mitscherlich,  E.,  7,  65,  77,  109,  no,  in, 

142,  187,315. 
Mond,  L.,  388. 
Monnet  and  Drury,  159. 
Mortimer,  144. 
Moulton,  Lord,  345,  347,  351,  371,  402, 

415,416,419. 
Miiller,  H.,  21,  34,  248. 
Mundella,  389. 
Musprat,  142. 
Musprat,  M.,  419. 


432         THE   BRITISH   COAL-TAR   INDUSTRY 


Natanson,  17,  159. 

Newlands,  J.  A.,  145. 

Newton,  J.,  &  Son,  132. 

Nicholson,  E.  C.,  21,  24,  64,  82,  86,  99, 
121,  124,  126,  157,  158,  160,  161, 
163,  187,  201,  237,  238,  253,  279, 
301. 

Nietzki,  R.,  80,  81,  194,  204. 

Nobel,  A.,  382. 


Ogilvie,  F.  G.,  349- 
Oldham,  G.  W.,  &  Co.,  132. 
Oldroyd,  M.,  423. 
Ormandy,  W.  R.,  335. 
Orr-Ewing,  John,  &  Co.,  134. 


Page,  F.  J.  M.,  145. 
Paquier,  381. 
Peachey,  315. 
Pedler,  A.,  145. 
Peligot,  1 10. 

Perkin,  F.  M.,  221,  298,  321,  336. 
Perkin,  T.  D.,  150,  243. 
Perkin,  W.  H.,  I,  46,  52,  54,  69,  75,  "i, 
118,  120,  121,  124,  125,  136,  141, 

145,  201,  232,  233,  234,  236,  237, 
238,  239,  240,  241,  242,  243,  244, 
246,  247,  248,  249,  250,  251,  252, 
254,  255,  257,  259,  260,  265,  269, 
270,  284,  294,  298,  301,  302,  316, 
321,  384,  390. 

Perkin,  W.  H.,  Jim.,  407,  419. 

Perkin  &  Sons,  152,  229,  237,  238,  239, 

240,  243,  250,  251,  253,  254,  260, 

300,  301,  303,  410. 
Persoz,  J.,  24,  34,  35. 
Phillips,  C.,  242. 
Poirrier  &  Chapat,  28,  61,  84,  115,  173, 

260. 

Pope,  W.J.,  315- 

Price,  A.  P.,  82,  242. 

Price,  D.,  157,  158,301. 

Priestley,  284. 

Pullar,  R.,  39,  124,  132,  152,  154,  234, 

240,  241,  298. . 

Pullar,  R.,  &   Son,  150,  152,  236,  240, 

241,  298. 
Pullar,  R.  D.,  420,  423. 


Ramsay,  W.,  284,  328. 

Rawson,  C.,  221. 

Read  Holliday  &  Sons,  193,  243,  301, 

426. 

Reichenbach,  176. 
Reid,  W.  F.,  332,  349- 


Renard  Freres,  17,  156,  159,  270,  316. 
Ripley,  E.,  &  Son,  132. 
Roberts,  A.,  349. 
Roberts,  Dale  &  Co.,  253,  301. 
Robiquet,  48,  53. 
Roemer,  93,  183. 
Roscoe,  H.  E.,  46,  71,  106,  365. 
Roussin,  Z.,  115,  118,  169. 
Royle,  T.,  135. 
Rudolph,  C.,  126. 
Runciman,  W.,  422. 

Runge,  F.,  4,  15,  34,  79,  142,  186,  235, 
236. 


Salvetat,  24. 

Samuelson,  B.,  389. 

Sapper,  E.,  213. 

Schering,  408. 

Scheurer-Kestner,  241. 

Schiendl,  169. 

Schimmel  &  Co.,  325. 

Schmitt,  R.,  34,  83. 

Schoenbein,  382. 

Schorlemmer,  52,  81,  254. 

Schultz,  A.,  40,  155,  163,  240. 

Schultz,  G.,  286. 

Schunck,  E.,  48,  49,  53,  91,  93,  183. 

Seidel,  P.,  215. 

Sharp,  M.  S.,  419,  420. 

Simon-Carves,  108. 

Simpson,  Maule  &   Nicholson,  77,  82, 

122,  126,  157,  158,  161,237,  238, 

242,  243,  253,  301,  303. 
Singer,  I.,  280,  294. 
Skraup,  119. 
Smiles,  215. 
Smith,  242,  301. 
Sobrero,  382. 
Soci6te    des    Usines    du    Rhone    (see 

Gilliard,  Monnet  &  Cartier). 
Spiller,  J.,  69,  145. 
Spiller,  W.,  237,  238,  243. 
Starck,  J.  D.,  242,  255,  256. 
St  Claire  Deville,  148. 
Stephenson,  R.,  284. 
Stevenson,  J.,  &  Co.,  133. 
Stirling,  W.,  &  Sons,  134. 
Strecker,  53. 


Tabourin,  241. 
Tedder,  A.  V.,  419. 
Templeton,  J.,  &  Co.,  133. 
Thenard,  P.,  147. 
Thomas,  E.,  254. 
Thompson,  W.  P.,  198. 
Thorp,  W.,  145. 


INDEX   OF   NAMES 


433 


Thorpe,  J.,  421. 

Tiemann,  120. 

Tilden,  W.  A.,  315,347,  348. 

Turkey-Red    Dyers'    Association,    305, 

312. 

Turner,  J.,  419. 
Tyndall,  284. 
Tyrer,  T.,  &  Co.,  219. 
Tyrer,  C.,  219. 
Tyrer,  T.,  309,  419- 

Unverdorben,  4,  5,  70,  77,  97,  142,  186. 

Van  Dorp,  211. 

Van'tHoff,  315. 

Verguin,  17,  81,  156,  159,  242,  243,  300, 

316. 

Verneuil,  381. 
Vidal,  R.,  194,  272. 
Vignon  &  Co.,  272. 


Walker,  W.,  &  Son,  132. 

Wanklyn,  86. 

Watts,  284. 

Weldon,  214. 

Williams,  C.  G.,  28,  101,  166,  242,  244, 

254,  301. 
Williams,     Thomas    &     Dower,     245, 

301. 

Wilton,  T.,  219. 
Winckler,     C.,     190,     213,     250,     255, 

256. 

Witt,  145. 
Witt,  O.  N.,  67,  69,  80,  99,  115,  1 1 8,  122, 

123,  195,  264,  301,  324. 
Wohler,  411. 
Worstall,  219. 
Wiirtz,  51,  178. 
Wynne,  192. 


Zinin,  4,  9,  65,  77,  142,  187,  238. 


28 


INDEX    OF   COLOURING    MATTERS 


Acid  green,  116,  192. 

magenta,  192,  228. 

violet,  192. 

yellow,  116,  122,  265. 
Acridine  orange,  194. 

yellow,  194. 

Aldehyde  green,  29,  84,  171,  260. 
Alizarin,  46,  54,  57,  91,  112,  113,  114, 
116,  122,  134,  136,  177,  178,  181, 
183,  194,  199,  228,  229,  245,  246, 
247,  248,  252,  260,  271,  290,  291, 
302,  305,  369,  412. 

blue,  94,  101,  265,  290. 

Bordeaux,  194. 

cyanine,  194. 

orange,  94,  290. 

saphirole,  194. 

viridine,  194. 
Alkali  blue,  83,  116. 
Alkaline  green,  63. 

Aniline     black,     40,     194,     254,     291, 
302. 

blue,  22,  43,  82,  88,  159,  161,  162,  163, 
164,  192,  228,  229. 

pink  (see  Safranine). 

purple  (see  Mauve). 

red  (see  Magenta). 

yellow,  122,  124,  192,  228,  253,  260. 
Anthracene  blue,  194. 
Anthrapurpurin,  92,  116,  181,  183. 
Auramine,  116,  192,  228,  230. 
Aurine,  34,  86,  113,  114,  II 6. 
Azodiphenyl  blue,  122. 
Azuline,  35,  83. 


Benzaldehyde  green,  84,  88,  90. 
Benzoflavine,  194. 
Biebrich  scarlet,  116,  123,  265. 
Bismarck  brown,  66,  99,  100,  116,  122, 

124,  192,  228,  253,  260. 
Blackley  blue,  116. 

red,  391. 

Bleu  de  Lyons  (see  Aniline  blue). 
Bleu  de  Paris,  24. 


Blue  black,  265. 
Bordeaux,  100,  116,  265,  291. 
Brilliant  green,  85,  88,  116,  228,  230. 
Britannia  violet,  28,  83,  166,  245,  251, 
252,  260. 


Cachou  de  Laval,  194,  265. 
Carminaphtha,  37. 
Chloramine  yellow,  193, 
Chrysoidine,  67,99,  Io°,  II5,  n6,  122, 

175,  192,  228,  265. 
Clayton  yellow,  193. 
Cochineal,  112,  158,  199. 
Coerulei'n,  265. 
Congo  red,  192,  265. 
Corraline  (see  Peonine). 
Crocein  scarlet,  116,  123,  192. 
Crysaniline  (see  Phosphine). 
Crystal  violet,  228,  230,  262. 
Cumidine  scarlet,  116. 
Cyanine,  101,  166,  167,  253,  301. 
Cyanosin,  116. 


Dahlia,  27,  45,  79,251. 
Diphenylamine  blue,  63,  116. 
orange,  116. 


Eosin,  95,  116,  122,  175,369- 
Erica,  193. 
Erythrosin,  116. 
Ethyl  violet,  166. 


Fast  red,  100,  265. 

yellow,  100. 
Field's  orange,  32. 
Flavaniline,  101,  126,  265. 
Flavopurpurin,  93,  116,  181. 
Fleur  de  Garance,  49,  178,  179. 
Fluorescein,  95. 
French  purple,  154. 
Fuchsine  (see  Magenta). 


434 


INDEX   OF   COLOURING   MATTERS 


435 


Gallein,  122,  265. 
Gallocyanin,  228. 
Garancine  (see  Fleur  de  Garance). 


Helianthine  (see  Orange  III.). 

Hofmann's  violet,  25,  44,  60,  83,  102, 
165,  173,  192,  228,  229,  230,  231, 
241,  244,  251,  260,  262,  279,  301. 


Immedial  black,  195. 

blue,  195. 

Imperial  violet,  24,  82,  159,  161,  163. 
Indigo  (artificial),  199,  204,  205,  216,  217, 
219,  265,  272,  273,  292,  308,  314, 
316,  323,  369,  412. 
(natural),  71,  97,  98,  117,  123,  199,  204, 

216,  217,  219,  309,  323. 
pure,  219. 
salt,  208,  215. 
Indoine  blue,  194. 
Indophenol,  115,  117,  123,  265. 
Indophor,  215. 
Induline,  116,  228,  253,  260. 

scarlet,  194. 

Iodine  green,  30,  63,  84,  166,  170,  173, 
228,  229,  230,  260. 


Janus  dyes,  193. 

Katigene  black,  195. 
brown,  195. 
green,  195. 

Lauth's  violet,  173,  264. 


Madder,  48,  55,  112,  178,  179,  '99,  245, 
302,  323- 

Magdala  red,  99,  169. 

Magenta,  16,  17,  18,  19,  20,  38,  43,  60, 
81,  102,  113,  114,  116,  122,  124, 
154,  156,  158,  161,  162,  192,  228, 
241,  242,  243,  244,  251,  253,  262, 
263,  270,  300,  301,  316,  369. 

Malachite  green,  63,  84,  116,  122,  192, 
205,  228,  230,  231,  262,  367,  412. 

Manchester  brown  (see  Bismarckbrown). 
yellow,  36,  loo,  116,  124,  228,  253,  260. 

Martius  yellow,  99,  169. 

Mauve,  5,  39,  76,  121,  124,  149,  151, 154, 
160,  161,  165,  174,  234,  239,  240, 
241,  242,  251,  254,  265,  270,  298, 
299,  3o 


Meister's  scarlet,  100. 
Meldola's  blue,  194. 
Metanil  yellow,  116. 
Methyl  green,  63. 
violet,  62,  88,  114,  116,  192,  228,  230, 

231,  244,  260,  262,  369. 
Methylene  blue,  101,  116,  122,  194,  228, 

230,  264,  271. 
Murexide,  269. 


Naphthalene  red,  170. 
Naphthazarin,  169. 
Naphthol  orange,  228,  265. 
yellow,  112,  114,  116,  265. 
Neutral  violet,  265. 
Nicholson's  blue,  24,  39,  83,  163. 
Night  blue,  228,  230,  231,  262. 
Nitroalizarin  (see  Alizarin  orange). 
Nitrosophenyline,  33. 


Opal  blue,  64. 
Orange  I.,  116. 
Orange  II.,  116. 
Orange  III.,  116. 
Orange  IV.,  116. 


Paranitraniline  red,  193,  291. 

Peonine,  34,  83. 

Perkin's  green,  31,  166,  252. 

violet  (see  Mauve). 
Phloxin,  96,  1 1 6. 
Phosphine,  21,  101,  126,  129,  164,  192, 

194,  228,  253,  260. 
Picric  acid,  33,  228,  253,  269. 
Pittacal,  176. 
Ponceau  2  R,  100,  265. 
Printline,  193,  278. 
Propiplic  acid,  206,  215. 
Prussian  blue,  269. 
Purpurin,  49,  92,  183. 
Pyrogene  blue,  195. 


Quinoline  blue  (see  Cyanine). 
red,  176. 


Regina,  163. 
Rhodamine,  194,  264. 
Rhoduline,  194. 
Roccellin,  116. 
Rosaniline  (see  Magenta). 
Rose  Bengal,  116. 
Roseine  (see  Magenta). 
Rosinduline,  194. 


436 


THE   BRITISH   COAL-TAR   INDUSTRY 


Rosolic  acid  (see  Aurine). 
Runge's  blue,  1 5,  79. 

Safranine,  31,  80,  116,  174, 175, 194,228, 

251,  265. 
Safrosin,  116. 
Soluble  blue,  24,  88,  163. 
Sun  yellow,  265. 


Tartrazine,  265. 
Thioflavine,  193. 
Tropaeoline  o,  67,  115,  122. 
Tropaeoline  oo,  67. 


Turmerine,  193. 

Tyrian  purple  (see  Mauve). 


Vermilline  scarlet,  113,  114,  116. 
Victoria  blue,  90,    116,   192,   230,  231, 

262. 

green,  84. 

Vidal  black,  195,  272. 
Violet  de  Paris,  173. 
Violine,  301. 


Xylidine  red,  168. 
scarlet  116,  192. 


TABULAR    AND    STATISTICAL 
INFORMATION 


Alizarin,  annual  production  of,  in 

1869-1873    ....       57 
chronological  history  of     .         .       53 
Alkali  trade  production,  1852-1861     317 
Anthracene  dyes,  British  patents, 

1855-1905    ....     271 
Azo  dyes,  British  patents,    1855- 

1905 272 

Badische  Anilin-  und  Soda-Fabrik, 

statistics  relating  to     .         .     220 
Bayer,  F.  &  Co.,  statistics  relating  to    224 
Coal,  distillation  products  of.         .2,  47 
products  obtainable  from  100  Ibs. 

of 13 

Coal-tar,  amount  distilled  for  colour- 
making  in  1890    .         .         .     286 
weight  of  various  dyes  obtain- 
able from     .        .        .        .114 
Coal-tar    dyes,    British    imports, 

1886-1900    ....     197 
British  patents,  1885-1905          .     270 
dyeing  power  of  colours  obtain- 
able from  i  ton  of  coal        .     114 
German  exports  of     .        .        .196 
imports  from  Germany  in  1913  .     319 
list  of  (in  1886),  arranged  accord- 
ing to  origin         .         .         .116 


Coal-tar  dyes,  list  of  those  produced 

by  Perkin  &  Sons        .         -251 
British    and   German,  used    in 

Britain  in  1865    .         .      133-136 

in  1900 197 

statistics  relating  to   .        .        .     383 
value  produced  in  1878       .        .       58 

Coal-tar  products,  British  imports 

and  exports  in  1909     .        .     285 
German  exports  of     .        .        .195 

German    colour  works,   statistics 

relating  to   .         .        .         .198 

Indigo,  value  of  world's  produc- 
tion     ...        71,  217,  220 

Indigo  dyes,  British  patents,  1855- 

1905     .        .        .        .        .270 

Madder,  annual  imports  of    .         55>  5^ 

Meister,  Lucius  &  Briining,  statis- 
tics relating  to     .        .     369,  370 

Patents,   numbers    taken   out   by 

British  and  German  firms  .     198 

Perfumes,  natural  and  synthetic    .     384 

Rosaniline  dyes,   British  patents, 

1885-1905    .        .         .        .271 

Sulphide  dyes         ....     273 

Sulphuric  acid  and  soda,   world's 

production  ....     384 


437 


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